Control of Air Pollution From Aircraft and Aircraft Engines; Emission Standards and Test Procedures

[Federal Register: September 30, 2003 (Volume 68, Number 189)]
[Proposed Rules]
[Page 56226-56251]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr30se03-35]

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ENVIRONMENTAL PROTECTION AGENCY
40 CFR Part 87
[AMS-FRL-7561-7]
RIN 2060-AK01

Control of Air Pollution From Aircraft and Aircraft Engines;
Emission Standards and Test Procedures

AGENCY: Environmental Protection Agency (EPA).
ACTION: Proposed rule.

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SUMMARY: In this action, we are proposing to amend the existing United
States regulations governing the exhaust emissions from new commercial
aircraft gas turbine engines. Under the authority of section 231 of the
Clean Air Act (CAA), the Environmental Protection Agency (EPA) is
proposing new emission standards for oxides of nitrogen
(NO_X) for newly certified commercial aircraft gas turbine
engines with rated thrust greater than 26.7 kilonewtons (kN). This
action proposes to adopt standards equivalent to the latest (effective
in 2004) NO_X standards of the United Nations International
Civil Aviation Organization (ICAO), and thereby bring the United States
emission standards into alignment with the internationally adopted
standards. In addition, today's action also would amend the test
procedures for gaseous exhaust emissions to correspond to recent
amendments to the ICAO test procedures for these emissions.
After December 31, 2003, the proposed NO_X standards
would apply to newly certified gas turbine engines--those engines
designed and certified after the effective date of the proposed
regulations (for purposes of this action, the date of manufacture of
the first individual production model means the date of type
certification). Since the proposed NO_X standards would apply
to only newly certified gas turbine engines, newly manufactured engines
(those engines built after the effective date of the proposed
regulations) would not have to meet these standards. Moreover, all
engines currently being built would not have to comply with the
NO_X emission standards that EPA is adopting today.
Today's proposed amendments to the emission test procedures are
those recommended by ICAO and are widely used by the aircraft engine
industry. Thus, today's action would establish consistency between U.S.
and international standards, requirements, and test procedures. Since
aircraft and aircraft engines are international commodities, there is
significant commercial benefit to consistency between U.S. and
international emission standards and control program requirements. In
addition, today's action ensures that domestic commercial aircraft
would meet the current international standards, and thus, the public
can be assured they are receiving the air quality benefits of the
international standards.

DATES: Comments: EPA requests comments on the proposed rulemaking by
December 15, 2003. More information about commenting on this action may
be found under Public Participation in the SUPPLEMENTARY INFORMATION
section and section I.C.
Hearing: We will hold a public hearing on November 13, 2003. The
hearing will start at 10 a.m. local time and continue until everyone
has had a chance to speak. If you want to testify at the hearing,
notify the contact person listed below at least ten days before the
hearing.

ADDRESSES: Comments: Comments may be submitted by mail to: Air Docket,
Environmental Protection Agency, Mailcode: 6102T, 1200 Pennsylvania
Ave., NW., Washington, DC, 20460, Attention Docket ID No. OAR 2002-
0030. Comments may also be submitted electronically, by facsimile, or
through hand delivery/courier. Follow the detailed instructions as
provided in section I.C. of the SUPPLEMENTARY INFORMATION section.
Hearing: The public hearing will be held at the Environmental
Protection Agency, EPA East Building, Room Number 1153, 1201
Constitution Avenue, NW., Washington, DC 20004, Telephone: (202) 564-
1682. See section VIII for more information about public hearings.

FOR FURTHER INFORMATION CONTACT: Mr. Bryan Manning, U.S. EPA, Office of
Transportation and Air Quality, Assessment and Standards Division, 2000
Traverwood, Ann Arbor, MI 48105. Telephone (734) 214-4832; Fax: (734)
214-4816, E-mail: manning.bryan@epa.gov.

SUPPLEMENTARY INFORMATION:

Outline of This Preamble

I. General Information
A. Regulated Entities
B. How Can I Get Copies of This Document and Other Related
Information?
1. Docket
2. Electronic Access
C. How and To Whom Do I Submit Comments?
1. Electronically
a. EPA Dockets
b. E-mail
c. Disk or CD ROM
2. By Mail
3. By Hand Delivery or Courier
4. By Facsimile
D. How Should I Submit CBI to the Agency?
E. What Should I Consider as I Prepare My Comments for EPA?
II. Introduction
A. A Brief History of EPA's Regulation of Aircraft Engine
Emissions
B. Interaction With the International Community
C. EPA's Responsibilities Under the Clean Air Act
III. Environmental Need for Control
A. Public Health Impacts
1. Ozone
a. What Are the Health Effects of Ozone Pollution?
b. Current and Projected 8-hour Ozone Levels
2. Particulate Matter
a. Health Effects of PM_2.5
b. Current and Projected Levels
B. Other Environmental Effects
1. Acid Deposition
2. Eutrophication and Nitrification
3. Plant Damage from Ozone
4. Visibility
C. Other Criteria Pollutants Affected by This Proposed Rule

IV. Description of Action

A. What Emission Standards Are Under Consideration?
1. Today's Proposed NO_X Standards
a. For Engines With a Pressure Ratio of 30 or less
i. For engines with a maximum rated output of more than 89.0 kN
ii. For engines with a maximum rated output of more than 26.7 kN
but not more than 89.0 kN
b. For Engines With A Pressure Ratio of More Than 30 But Less
than 62.5
i. For engines with a maximum rated output of more than 89.0 kN
ii. For engines with a maximum rated output of more than 26.7 kN
but not more than 89.0 kN
c. For Engines With a Pressure Ratio of 62.5 or More
2. Proposed NO_X Standards of Newly Certified Mid- and
High-Thrust Engines
3. Proposed NO_X Standards for Newly Certified Low-
Thrust Engines
4. Rationale of Proposed NO_X Standards for Newly
Certified Low-, Mid-, and High-Thrust Engines
5. Future NO_X Standards for Newly Certified Low-,
Mid-, and High-Thrust Engines
B. Already Certified, Newly Manufactured Engines
1. Effect of Market Forces
2. Impact of Existing Fleet Aircraft
3. Request for Comment on Applying the Proposed NO_X
Standards to Already Certified Engines
C. Amendments to Criteria on Calibration and Test Gases for
Gaseous Emissions Test and Measurement Procedures
D. Correction of Exemptions for Very Low Production Models
V. Coordination with FAA

[[Page 56227]]

VI. Possible Future Aviation Emissions Reduction (EPA/FAA Voluntary
Aviation Emissions Reduction Initiative)
VII. Regulatory Impacts
VIII. Public Participation
A. How Do I Submit Comments?
B. Will There Be a Public Hearing?
IX. Statutory Authority
X. Statutory and Executive Orders Review
A. Executive Order 12866: Regulatory Planning and Review
B. Paperwork Reduction Act
C. Regulatory Flexibility Act
D. Unfunded Mandates Reform Act
E. Executive Order 13132: Federalism
F. Executive Order 13175: Consultation and Coordination with
Indian Tribal Governments
G. Executive Order 13045: Protection of Children from
Environmental Health & Safety Risks
H. Executive Order 13211: Actions that Significantly Affect
Energy Supply, Distribution, or Use
I. National Technology Transfer Advancement Act

I. General Information

A. Regulated Entities

Entities potentially regulated by this action are those that
manufacture and sell commercial aircraft engines and aircraft in the
United States, and the owners/operators of such aircraft (and
accompanying engines) in the United States. Regulated categories
include:

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NAICS \a\ Examples of potentially affected
Category codes SIC codes \b\ entities
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Industry.............................. 336412 3724 Manufacturers of new aircraft engines.
Industry.............................. 336411 3721 Manufacturers of new aircraft.
Industry.............................. 481 4512 Scheduled air carriers, passenger and
freight.
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\a\ North American Industry Classification System (NAICS).
\b\ Standard Industrial Classification (SIC) system code.

This table is not intended to be exhaustive, but rather provides a
guide for readers regarding entities likely to be regulated by this
action. This table lists the types of entities that EPA is now aware
could potentially be regulated by this action. Other types of entities
not listed in the table could also be regulated. To determine whether
your activities are regulated by this action, you should carefully
examine the applicability criteria in 40 CFR 87.20. If you have any
questions regarding the applicability of this action to a particular
entity, consult the person listed in the preceding FOR FURTHER
INFORMATION CONTACT section.

B. How Can I Get Copies of This Document and Other Related Information?

1. Docket. EPA has established an official public docket for this
action under Docket ID No. OAR 2002-0030. The official public docket is
the collection of materials that is available for public viewing at the
Air Docket in the EPA Docket Center, (EPA/DC) EPA West, Room B102, 1301
Constitution Ave., NW., Washington, DC. The EPA Docket Center Public
Reading Room is open from 8:30 a.m. to 4:30 p.m., Monday through
Friday, excluding legal holidays. The telephone number for the Reading
Room and the Air Docket is (202) 566-1742. You may be charged a
reasonable fee for photocopying docket materials, as provided in 40 CFR
part 2.
2. Electronic Access. You may access this Federal Register document
electronically through the EPA Internet under the ``Federal Register''
listings at http://www.epa.gov/fedrgstr/.
An electronic version of the public docket is available through
EPA's electronic public docket and comment system, EPA Dockets. You may
use EPA Dockets at http://www.regulations.gov/ to submit or view public
comments, access the index listing of the contents of the official
public docket, and to access those documents in the public docket that
are available electronically. Once in the system, select ``search,''
then key in the appropriate docket identification number.
Certain types of information will not be placed in the EPA Dockets.
Information claimed as confidential business information (CBI) and
other information whose disclosure is restricted by statute, which is
not included in the official public docket, will not be available for
public viewing in EPA's electronic public docket. EPA's policy is that
copyrighted material will not be placed in EPA's electronic public
docket but will be available only in printed, paper form in the
official public docket. To the extent feasible, publicly available
docket materials will be made available in EPA's electronic public
docket. When a document is selected from the index list in EPA Dockets,
the system will identify whether the document is available for viewing
in EPA's electronic public docket. Although not all docket materials
may be available electronically, you may still access any of the
publicly available docket materials through the docket facility
identified in section I.B.1. EPA intends to work towards providing
electronic access to all of the publicly available docket materials
through EPA's electronic public docket.
For public commenters, it is important to note that EPA's policy is
that public comments, whether submitted electronically or in paper,
will be made available for public viewing in EPA's electronic public
docket as EPA receives them and without change, unless the comment
contains copyrighted material, CBI, or other information whose
disclosure is restricted by statute. When EPA identifies a comment
containing copyrighted material, EPA will provide a reference to that
material in the version of the comment that is placed in EPA's
electronic public docket. The entire printed comment, including the
copyrighted material, will be available in the public docket.
Public comments submitted on computer disks that are mailed or
delivered to the docket will be transferred to EPA's electronic public
docket. Public comments that are mailed or delivered to the Docket will
be scanned and placed in EPA's electronic public docket. Where
practical, physical objects will be photographed, and the photograph
will be placed in EPA's electronic public docket along with a brief
description written by the docket staff.
For additional information about EPA's electronic public docket
visit EPA Dockets online or see 67 FR 38102, May 31, 2002.

C. How and To Whom Do I Submit Comments?

You may submit comments electronically, by mail, by facsimile, or
through hand delivery/courier. To ensure proper receipt by EPA,
identify the appropriate docket identification number in the subject
line on the first page of your comment. Please ensure that your
comments are submitted within the specified comment period. Comments
received after the close of the comment period will be marked ``late.''
EPA is not required to consider these late comments.
1. Electronically. If you submit an electronic comment as
prescribed below, EPA recommends that you include your name, mailing
address, and an e-mail address or other contact

[[Page 56228]]

information in the body of your comment. Also include this contact
information on the outside of any disk or CD ROM you submit, and in any
cover letter accompanying the disk or CD ROM. This ensures that you can
be identified as the submitter of the comment and allows EPA to contact
you in case EPA cannot read your comment due to technical difficulties
or needs further information on the substance of your comment. EPA's
policy is that EPA will not edit your comment, and any identifying or
contact information provided in the body of a comment will be included
as part of the comment that is placed in the official public docket,
and made available in EPA's electronic public docket. If EPA cannot
read your comment due to technical difficulties and cannot contact you
for clarification, EPA may not be able to consider your comment.
a. EPA Dockets. Your use of EPA's electronic public docket to
submit comments to EPA electronically is EPA's preferred method for
receiving comments. Go directly to EPA Dockets at http://www.epa.gov/
edocket, and follow the online instructions for submitting comments.
To access EPA's electronic public docket from the EPA Internet Home Page,
select ``Information Sources,'' ``Dockets,'' and ``EPA Dockets.'' Once
in the system, select ``search,'' and then key in Docket ID No. OAR
2002-0030. The system is an ``anonymous access'' system, which means
EPA will not know your identity, e-mail address, or other contact
information unless you provide it in the body of your comment.
b. E-mail. Comments may be sent by electronic mail (e-mail) to
aircraft@epa.gov, Attention Docket ID No. OAR 2002-0030. In contrast to
EPA's electronic public docket, EPA's e-mail system is not an
``anonymous access'' system. If you send an e-mail comment directly to
the Docket without going through EPA's electronic public docket, EPA's
e-mail system automatically captures your e-mail address. E-mail
addresses that are automatically captured by EPA's e-mail system are
included as part of the comment that is placed in the official public
docket, and made available in EPA's electronic public docket.
c. Disk or CD ROM. You may submit comments on a disk or CD ROM that
you mail to the mailing address identified in section I.C.2. These
electronic submissions will be accepted in WordPerfect or ASCII file
format. Avoid the use of special characters and any form of encryption.
2. By Mail. Send your comments to: Air Docket, Environmental
Protection Agency, Mailcode: 6102T, 1200 Pennsylvania Ave., NW.,
Washington, DC, 20460, Attention Docket ID No. OAR 2002-0030.
3. By Hand Delivery or Courier. Deliver your comments to: EPA
Docket Center, (EPA/DC) EPA West, Room B102, 1301 Constitution Ave.,
NW., Washington, DC 20004, Attention Docket ID No. OAR 2002-0030. Such
deliveries are only accepted during the Docket's normal hours of
operation as identified in section I.B.1.
4. By Facsimile. Fax your comments to: (202) 566-1741, Attention
Docket ID. No. OAR 2002-0030.

D. How Should I Submit CBI to the Agency?

Do not submit information that you consider to be CBI
electronically through EPA's electronic public docket or by e-mail.
Send or deliver information identified as CBI only to the contact
person listed in the FOR FURTHER INFORMATION CONTACT section. You may
claim information that you submit to EPA as CBI by marking any part or
all of that information as CBI (if you submit CBI on disk or CD ROM,
mark the outside of the disk or CD ROM as CBI and then identify
electronically within the disk or CD ROM the specific information that
is CBI). Information so marked will not be disclosed except in
accordance with procedures set forth in 40 CFR part 2.
In addition to one complete version of the comment that includes
any information claimed as CBI, a copy of the comment that does not
contain the information claimed as CBI must be submitted for inclusion
in the public docket and EPA's electronic public docket. If you submit
the copy that does not contain CBI on disk or CD ROM, mark the outside
of the disk or CD ROM clearly that it does not contain CBI. Information
not marked as CBI will be included in the public docket and EPA's
electronic public docket without prior notice. If you have any
questions about CBI or the procedures for claiming CBI, please consult
the person identified in the FOR FURTHER INFORMATION CONTACT section.

E. What Should I Consider as I Prepare My Comments for EPA?

You may find the following suggestions helpful for preparing your
comments:
1. Explain your views as clearly as possible.
2. Describe any assumptions that you used.
3. Provide any technical information and/or data you used that
support your views.
4. If you estimate potential burden or costs, explain how you
arrived at your estimate.
5. Provide specific examples to illustrate your concerns.
6. Offer alternatives.
7. Make sure to submit your comments by the comment period deadline
identified.
8. To ensure proper receipt by EPA, identify the appropriate docket
identification number in the subject line on the first page of your
response. It would also be helpful if you provided the name, date, and
Federal Register citation related to your comments.

II. Introduction

A. Brief History of EPA's Regulation of Aircraft Engine Emissions

Section 231(a)(2)(A) of the Clean Air Act (CAA) directs the EPA
Administrator to ``issue proposed emission standards applicable to the
emission of any air pollutant from any class or classes of aircraft or
aircraft engines which in his judgment causes, or contributes to, air
pollution which may reasonably be anticipated to endanger public health
or welfare'' (42 U.S.C. 7571(a)(2)(A)). Under this authority EPA has
conducted several rulemakings since 1973 establishing emission
standards and related requirements for several classes (commercial and
general aviation engines) of aircraft and aircraft engines. Most
recently, in 1997 EPA promulgated NO_X emission standards for
newly manufactured gas turbine engines (those engines built after the
effective date of the regulations or already certified engines) and for
newly certified gas turbine engines (those engines designed and
certified after the effective date of the regulations\1\).\2\ In
addition, EPA promulgated a carbon monoxide (CO) emission standard for
newly manufactured gas turbine engines in this same 1997 rulemaking. At
the time, the 1997 rulemaking established consistency between the U.S.
and international standards. (See 40 CFR part 87 for a description of
EPA's aircraft engine emission control requirements and 14 CFR part 34
for the Secretary of Transportation's regulations for ensuring
compliance with these standards in accordance with section 232 of the
Clean Air Act.)
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\1\ Throughout this notice, the date of manufacture of the first
individual production model means the date of type certification.
\2\ U.S. EPA, ``Control of Air Pollution from Aircraft and
Aircraft Engines; Emission Standards and Test Procedures;'' Final
Rule, 62 FR 25356, May 8, 1997.

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[[Page 56229]]

B. Interaction With the International Community

Since publication of the initial standards in 1973, EPA, together
with the Federal Aviation Administration (FAA), has worked with the
International Civil Aviation Organization (ICAO) on the development of
international aircraft engine emission standards. ICAO was established
in 1944 by the United Nations (by the Convention on International Civil
Aviation, the ``Chicago Convention'') ``* * * in order that
international civil aviation may be developed in a safe and orderly
manner and that international air transport services may be established
on the basis of equality of opportunity and operated soundly and
economically.'' \3\ ICAO's responsibilities include developing aircraft
technical and operating standards, recommending practices, and
generally fostering the growth of international civil aviation.
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\3\ ICAO, ``Convention on International Civil Aviation,'' Sixth
Edition, Document 7300/6, 1980. Copies of this document can be
obtained from the ICAO Web site located at http://www.icao.int.
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In 1972 at the United Nations Conference on the Human Environment,
ICAO's position on the human environment was developed to be the
following: ``[i]n fulfilling this role ICAO is conscious of the adverse
environmental impact that may be related to aircraft activity and its
responsibility and that of its member States to achieve maximum
compatibility between the safe and orderly development of civil
aviation and the quality of the human environment.'' Also, in 1972 ICAO
established the position to continue ``* * * with the assistance and
cooperation of other bodies of the Organization and other international
organizations * * * the work related to the development of Standards,
Recommended Practices and Procedures and/or guidance material dealing
with the quality of the human environment * * *.'' \4\
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\4\ International Civil Aviation Organization (ICAO), Foreword
of ``Aircraft Engine Emissions,'' International Standards and
Recommended Practices, Environmental Protection, Annex 16, Volume
II, Second Edition, July 1993. Copies of this document can be
obtained from the ICAO Web site located at http://www.icao.int.
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The United States is one of 188 participating member States of
ICAO.\5\ Under the basic ICAO treaty established in 1944 (the Chicago
Convention), a participating nation which elects not to adopt the ICAO
standards must provide a written explanation to ICAO describing why a
given standard is impractical to comply with or not in their national
interest.\6\ ICAO has no punitive powers for states that elect not to
adopt ICAO standards. ICAO standards require States to provide written
notification and failure to provide such notification could have
negative consequences as detailed below.
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\5\ As of June 20, 2002 there were 188 Contracting States
according to the ICAO Web site located at http://www.icao.int.
\6\ Text of Article 38 of Chicago Convention: Any State which
finds it impracticable to comply in all respects with any such
international standard or procedure, or to bring its own regulations
or practices into full accord with any international standard or
procedure after amendment of the latter, or which deems it necessary
to adopt regulations or practices differing in any particular
respect from those established by an international standard, shall
give immediate notification to the International Civil Aviation
Organization of the differences between its own practice and that
established by the international standard. * * * In any such case,
the Council shall make immediate notification to all other states of
the difference which exists between one or more features of an
international standard and the corresponding national practice of
that State.
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If a Contracting State files a written notification indicating that
it does not meet ICAO standards, other Contracting States are absolved
of their obligations to ``recognize as valid'' the certificate of
airworthiness issued by that Contracting States, since that certificate
will not have been issued under standards ``equal to or above'' ICAO
standards. In other words, other Contracting States do not have to
allow aircraft belonging to that Contracting State to travel through
their airspace.\7\ Further, if it fails to file a written notification,
it will be in default of its obligations, and risks mandatory exclusion
of its aircraft from the airspace of other Contracting States and the
loss of its voting power in the Assembly and Council.\8\
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\7\ Text of Article 33 of Chicago Convention: Certificates of
airworthiness and certificates of competency and licenses issued or
rendered valid by the contracting State in which the aircraft is
registered, shall be recognized as valid by the other contracting
States, provided that the requirements under which such certificates
or licenses were issued or rendered valid are equal to or above the
minimum standards which may be established from time to time
pursuant to this Convention.
\8\ Articles 87 and 88 of Chicago Convention.
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The ICAO Council's Committee on Aviation Environmental Protection
(CAEP) undertakes ICAO's technical work in the environmental field. The
CAEP is responsible for evaluating, researching, and recommending
measures to the ICAO Council that address the environmental impact of
international civil aviation. CAEP is composed of various Study Groups,
Work Groups, Committees and other contributing memberships that include
atmospheric, economic, aviation, environmental, and other professionals
committed to ICAO's previously stated position regarding aviation and
the environment. At CAEP meetings, the United States is represented by
the FAA, which plays an active role at these meetings (see section V
for further discussion of FAA's role). EPA is a principal participant
in the development of U.S. policy in ICAO/CAEP and other international
venues. (EPA assists and technically advises FAA on aviation emissions
matters.) If the ICAO Council adopts a CAEP proposal to adopt a new
environmental standard, it then becomes part of the ICAO standards and
recommended practices (Annex 16 to the Chicago Convention).\9\
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\9\ ICAO, ``Aircraft Engine Emissions,'' International Standards
and Recommended Practices, Environmental Protection, Annex 16,
Volume II, Second Edition, July 1993. Copies of this document can be
obtained from ICAO (http://www.icao.int).
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On June 30, 1981, the ICAO Council adopted its first international
standards and recommended practices covering aircraft engine
emissions.\10\ These standards limit aircraft engine emissions of
NO_X, CO, and hydrocarbons (HC), in relation to other engine
performance parameters, and are commonly known as stringency standards.
On March 24, 1993, the ICAO Council approved a proposal adopted at the
second meeting of the CAEP (CAEP/2) to tighten the original
NO_X standard by 20 percent and amend the test procedures. At
the next CAEP meeting (CAEP/3) in December 1995, the CAEP recommended a
further tightening of 16 percent and additional test procedure
amendments, but on March 20, 1997 the ICAO Council rejected this
stringency proposal and approved only the test procedure amendments. At
its next meeting (CAEP/4) in April 1998, the CAEP adopted a similar 16
percent NO_X reduction proposal, which the ICAO Council
approved on February 26, 1999.\11\ The CAEP/4 16 percent NO_X
reduction standard applies to new engine designs certified after
December 31, 2003 (applies only to newly certified engines).\12\
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\10\ ICAO, Foreword of ``Aircraft Engine Emissions,''
International Standards and Recommended Practices, Environmental
Protection, Annex 16, Volume II, Second Edition, July 1993. Copies
of this document can be obtained from ICAO (http://www.icao.int).
\11\ International Civil Aviation Organization (ICAO), Aircraft
Engine Emissions, Annex 16, Volume II, Second Edition, July 1993,
Amendment 4 effective on July 19, 1999. Copies of this document can
be obtained from ICAO (http://www.icao.int).
\12\ These NO_X standards will be interchangeably be
referred to as the 1998 CAEP/4 standards and the 1999 ICAO standards
throughout this notice.
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As discussed earlier, in 1997 EPA amended its regulations to adopt
the

[[Page 56230]]

1981 ICAO NO_X and CO emission standards, as well as the
NO_X emission standards and test procedures revised by ICAO
in 1993. As discussed above, the U.S. has an obligation under the
Convention on International Civil Aviation to notify ICAO regarding
differences between U.S. standards and ICAO standards, and to provide
notification on the date by which the program requirements will be
consistent. In response to the recent actions by ICAO and for the
reasons discussed below, EPA proposes to adopt standards equivalent to
ICAO's 1999 amendment to the NO_X emission standard, the test
procedure changes approved by ICAO in 1997, and other technical
amendments to further align EPA and ICAO requirements.

C. EPA's Responsibilities Under the Clean Air Act

As discussed earlier, section 231 of the CAA directs EPA, from time
to time, to propose aircraft engine emission standards for any air
pollutant that could reasonably endanger public health and welfare. In
addition, EPA is required to ensure such standards' effective dates
permit the development of necessary technology, giving appropriate
consideration to compliance cost. Also, EPA must consult with the FAA
concerning aircraft safety before proposing or promulgating emission
standards. (See section V of today's proposal for further discussion of
EPA's coordination with FAA and FAA's responsibilities under the CAA.)
In addition, section 233 of the CAA vests authority to implement
emission standards for aircraft engines only in EPA.\13\ States are
preempted from taking independent action. Thus, while many states are
implementing control programs to reduce mobile source emissions, EPA
has the authority to establish an emission control program for aircraft
engines.
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\13\ CAA section 233 entitled ``State Standards and Controls''
states that ``No State or political subdivision thereof may adopt or
attempt to enforce any standard respecting emissions of any air
pollutant from any aircraft or engine thereof unless such standard
is identical to a standard applicable to such aircraft under this
part.''
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III. Environmental Need for Control

As mentioned above, section 231(a)(2)(A) of the CAA authorizes the
EPA Administrator to, from time to time, revisit emission standards for
aircraft engine emissions ``* * * which in his judgment causes, or
contributes to air pollution which may * * * endanger public health or
welfare.'' In judging the need for the NO_X standard
promulgated in today's action, the Administrator has determined (1)
That the public health and welfare is endangered in several air quality
regions by violation of the National Ambient Air Quality Standards
(NAAQS) for ozone (NO_X contributes to the formation of
ozone); and (2) that airports and aircraft are now or are projected to
be, increasing sources of emissions of NO_X in some of the
air quality control regions in which the NAAQS are being violated.
Nationwide, aircraft account for about 1 percent of the
NO_X emissions from mobile sources.\14\ Commercial aircraft
emissions contribute from 74 to 99 percent of the NO_X
aircraft emissions in the U.S. (Aircraft emissions sources include
aircraft types used for public, private, and military purposes as
follows: commercial aircraft, air taxis, general aviation, and military
aircraft.\15\ The current nationwide aircraft emission estimates have
limitations for military aircraft emissions. Therefore, the estimated
range of commercial aircraft's emissions contribution to nationwide
aircraft NO_X described above is reflective of earlier and
current estimates for military aircraft emissions).
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\14\ U.S. EPA, ``Average Annual Emissions, All Criteria
Pollutants Years Including 1980, 1985, 1989-2001,'' February 2003.
This document is available at http://www.epa.gov/ttnchie1/trends/. A
copy of this document can also be found in Docket No. OAR-2002-30.
Documentation for these estimates can be accessed at http://www.epa.gov/
ttn/chief/net/index.html#1999: U.S. EPA, ``Documentation
for Aircraft, Commercial Marine Vessel, Locomotive, and Other
Nonroad Components of the National Emissions Inventory, Volume I--
Methodology,'' November 11, 2002. A copy of this document can also
be found in Docket No. OAR-2002-30.
\15\ Commercial aircraft include those aircraft used for
scheduled service transporting passengers, freight, or both. Air
taxis also fly scheduled service carrying passengers, freight or
both, but usually are smaller aircraft and operate on a more limited
basis than commercial carriers. General aviation includes most other
aircraft used for recreational flying and personal transportation.
Aircraft that support business travel, usually on an unscheduled
basis, are included in the category of general aviation. Military
aircraft cover a wide range of sizes, uses, and operating missions.
While they are often similar to civil aircraft, they are handled
separately because they typically operate exclusively out of
military bases and frequently have distinctive flight profiles.
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Commercial aircraft emissions are projected to be a growing segment
of the transportation sector's emission inventory. This growth in
commercial aircraft emissions is expected to occur at a time when other
significant mobile and stationary sources are drastically reducing
emissions, thereby accentuating the growth in aircraft emissions. For
instance, from a local/regional perspective the 1999 EPA study,
Evaluation of Air Pollutant Emissions from Subsonic Commercial Jet
Aircraft, reported that from 1990 to 2010 increases in commercial
aircraft NO_X emissions for the ten cities studied (19
airport facilities with significant commercial jet aircraft activity
were identified within these selected cities) are expected to range
from 50 to 110 percent.\16\ As an average for the ten cities,
commercial aircraft's contribution to regional mobile source
NO_X was anticipated to increase from about 2 percent in 1990
to about 5 percent in 2010. In addition, the study showed that in 2010
commercial aircraft are projected to contribute as much as 10 percent
of total regional mobile source NO_X emissions in at least
two of the cities studied.\17\
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\16\ This study (EPA 420-R-99-013, April 1999) is available at
http://www.epa.gov/otaq/aviation.htm. It can also be found in Docket
No. OAR-2002-0030.
\17\ Based on the one-hour ozone standard, nine of the ten
metropolitan areas are currently not in attainment of NAAQS for
ozone; the tenth city has attained the ozone standard and is
considered an ozone ``maintenance'' area. See section III.A.1. of
this proposal for further discussion on the ozone NAAQs. Also, for
more detailed information on the 8-hour ozone standard, see the
following EPA Web sites: http://www.epa.gov/airlinks/ozpminfo.html,
http://www.epa.gov/airlinks/airlinks4.html or http://www.epa.gov/
http://www.epa.gov/ttn/naaqs/ozone/o3imp8hr.
EPA has not yet designated areas for the 8-hour standard.
---------------------------------------------------------------------------

(The above projections were made prior to the tragic events of
September 11, 2001, and the subsequent economic downturn. A January
2003 report by the Department of Transportation indicated that the
combination of the September 11, 2001 terrorist attacks and a cut-back
in business travel had a significant and perhaps long-lasting effect on
air traffic demand.\18\ However, the FAA expects the demand for air
travel to recover, and then continue a long-term trend of annual growth
in the United States.\19\ Recently, FAA reported that flights of
commercial air carriers will increase by 18 percent from 2002 to 2010
and 45 percent from 2002 to 2020.\20\ For a

[[Page 56231]]

comparison of an earlier (pre-9/11) FAA activity forecast to a recent
(post-9/11) forecast, see the below table. We request comment on the
effect that September 11, 2001, and the subsequent economic downturn
have had on the projected growth of commercial aircraft emissions. Your
comments will be most useful if you include appropriate and detailed
supporting data and analysis.)
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\18\ U.S. Department of Transportation, Office of Inspector
General, ``Airline Industry Metrics,'' CC-2203-007, January 7, 2003.
A copy of this document can be found in Docket No. OAR-2002-0030.
\19\ U.S. General Accounting Office, ``Aviation and the
Environment: Strategic Framework Needed to Address Challenges Posed
by Aircraft Emissions,'' GAO-03-252, February 2003. This document is
available at http://www.gao.gov/cgi-bin/getrpt?GAO-03-252,
and it can also be found in the Docket No. OAR-2002-0030.
\20\ The flight forecast data is based on FAA's Terminal Area
Forecast System (TAFS). TAFs is the official forecast of aviation
activity at FAA facilities. This includes FAA-towered airports,
federally-contracted towered airports, nonfederal towered airports,
and many non-towered airports. For detailed information on TAFS and
the air carrier activity forecasts see the following FAA Web site:
http://www.apo.data.faa.gov/faatafall.HTM. As of May 1,
2003, the aviation forecasts contained in TAFS for Fiscal Years 2002-2020
included the impact of the terrorists' attacks of September 11, 2001
and the recent economic downturn. However, these projections did not
fully reflect the ongoing structural changes occurring within the
aviation industry. A copy of the May 1, 2003 forecast summary report
for air carrier activity can be found in Docket No. OAR-2002-0030.

Table III-1.--FAA Terminal Area Forecast Summary Report of Nationwide Air Carrier Operations \21\
----------------------------------------------------------------------------------------------------------------
Percent change Percent change
Air carrier 12/14/00 Air carrier 5/1/03
Year operations 12/ forecast operations 5/1/ forecast
14/00 forecast between years 03 forecast between years
(pre-9/11) listed (post-9/11) listed
----------------------------------------------------------------------------------------------------------------
1999............................................ 15,127,419 .............. 14,776,055 ..............
2000............................................ 15,476,135 2.3 15,265,682 3.3
2001............................................ 15,819,505 2.2 14,807,303 -3.0
2002 a.......................................... 16,210,777 2.5 13,255,837 -10
2005............................................ 17,455,705 7.6 13,918,058 5.0
2010............................................ 19,664,128 14 15,608,349 13
2015............................................ 22,004,067 12 17,372,200 11
2020............................................ N/A b -- 19,249,778 11
----------------------------------------------------------------------------------------------------------------
a The change in operations from 2000 to 2002 was +4.7% for the 12/14/00 forecast, and it was -13% for the 5/1/03
forecast.
b N/A = Not available.

Air pollutants resulting from airport operations are emitted from
several types of sources: aircraft main engines and auxiliary power
units (APUs); ground support equipment (GSE), which include vehicles
such as aircraft tugs, baggage tugs, fuel trucks, maintenance vehicles,
and other miscellaneous vehicles used to support aircraft operations;
ground access vehicles (GAV), which include vehicles from off-site used
by passengers, employees, freight operators, and other persons
utilizing an airport. EPA's previous estimates show aircraft engines
comprise approximately 45 percent of total air pollutant emissions from
airport operations; GAV account for another 45 percent, and APUs and
GSE combined make up the remaining 10 percent.\22\ Since EPA has
established stringent emission standards for GAVs and other motor
vehicles that will be manufactured and introduced into commerce in
future years, overall emissions from these vehicles will continue to
decline for many years.
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\21\ A copy of FAA's 12/14/00 forecast summary report (from
TAFS) for air carrier activity can be found in Docket No. OAR-2002-
0030.
\22\ The California FIP, signed by the Administrator 2/14/95, is
located in EPA Air Docket A-94-09, item number V-A-1. The FIP was
vacated by an act of Congress before it became effective.
In addition, the 1997 EPA Draft Final Report entitled,
``Analysis of Techniques to Reduce Air Emission at Airports''
(prepared by Energy and Environmental Analysis, Inc), it was
estimated that for the four airports studied (which are large air
traffic hubs) on average aircraft compromise approximately 35
percent of NO_X emissions from airport operations; GAV
account for another 35 percent, and APUs and GSE contribute about 15
percent each for the remaining 30 percent. This document can be
found in Docket No. OAR-2002-0030.
---------------------------------------------------------------------------

The emissions from aircraft engines that are being directly
controlled by the standards proposed in this rulemaking are
NO_X. As discussed later in this section, NO_X
emissions at low altitude also react in the atmosphere to form
secondary particulate matter (PM_2.5),\23\ which is namely
ammonium nitrate, and thus, secondary PM would be effected as a
consequence of the proposed standards. Adopting standards equivalent to
the latest ICAO NO_X emission standards and the related ICAO
test procedures would help in achieving and/or maintaining compliance
with the NAAQS for ozone (O₃)and PM.
---------------------------------------------------------------------------

\23\ As described later in section III.A.2., fine particles
refer to those particles with an aerodynamic diameter less than or
equal to a nominal 2.5 micrometers (also known as PM_2.5).
---------------------------------------------------------------------------

There are about 111 million people living in counties with
monitored concentrations exceeding the 8-hour ozone NAAQS , and over 65
million people living in counties with monitored PM_2.5
levels exceeding the PM_2.5 NAAQS. Figure III.-1 illustrates
the widespread nature of these problems. Shown in this figure are
counties exceeding either or both of the two NAAQS plus mandatory
Federal Class I areas, which have particular needs for reductions in
atmospheric haze. A discussion of the adverse effects on public health
and welfare associated with these pollutants is provided below.

[[Page 56232]]

[GRAPHIC]
[TIFF OMITTED]
TP30SE03.000

A. Public Health Impacts

1. Ozone
a. What are the health effects of ozone pollution? Ground-level
ozone pollution (sometimes called ``smog'') is formed by the reaction
of nitrogen oxides (NO_X) and volatile organic compounds
(VOC) in the atmosphere in the presence of heat and sunlight.\24\ Ozone
can irritate the respiratory system, causing coughing, throat
irritation, and/or uncomfortable sensation in the chest.
25,26 Ozone can reduce lung function and make it more
difficult to breathe deeply, and breathing may become more rapid and
shallow than normal, thereby limiting a person's normal activity. Ozone
also can aggravate asthma, leading to more asthma attacks that require
a doctor's attention and/or the use of additional medication. In
addition, ozone can inflame and damage the lining of the lungs, which
may lead to permanent changes in lung tissue, irreversible reductions
in lung function, and a lower quality of life if the inflammation
occurs repeatedly over a long time period (months, years, a lifetime).
People who are of particular concern with respect to ozone exposures
include children and adults who are active outdoors. Those people
particularly susceptible to ozone effects are people with respiratory
disease, such as asthma, and people with unusual sensitivity to ozone,
and children. Beyond its human health effects, ozone has been shown to
injure plants, which has the effect of reducing crop yields and
reducing productivity in forest ecosystems.27,28
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\24\ U.S. EPA, ``Nitrogen Oxides: Impacts on Public Health and
the Environment,'' EPA 452/R-97-002, August 1997. A copy of this
document is available in Docket No. OAR 2002-0030.
\25\ U.S. EPA (1996). Air Quality Criteria for Ozone and Related
Photochemical Oxidants, EPA/600/P-93/004aF. Docket No. A-99-06.
Document Nos. II-A-15 to 17.
\26\ U.S. EPA. (1996). Review of National Ambient Air Quality
Standards for Ozone, Assessment of Scientific and Technical
Information, OAQPS Staff Paper, EPA-452/R-96-007. Docket No. A-99-
06. Document No. II-A-22.
\27\ U.S. EPA (1996). Air Quality Criteria for Ozone and Related
Photochemical Oxidants, EPA/600/P-93/004aF. Docket No. A-99-06.
Document Nos. II-A-15 to 17.
\28\ U.S. EPA. (1996). Review of National Ambient Air Quality
Standards for Ozone, Assessment of Scientific and Technical
Information, OAQPS Staff Paper, EPA-452/R-96-007. Docket No. A-99-
06. Document No. II-A-22.
---------------------------------------------------------------------------

The 8-hour ozone standard, established by EPA in 1997, is based on
well-documented science demonstrating that more people are experiencing
adverse health effects at lower levels of exertion, over longer
periods, and at lower ozone concentrations than addressed by the one-
hour ozone standard. (See, e.g., 62 FR 38861-38862, July 18, 1997). The
8-hour standard addresses ozone exposures of concern for the general
population and populations most at risk, including

[[Page 56233]]

children active outdoors, outdoor workers, and individuals with pre-
existing respiratory disease, such as asthma.
There has been new research that suggests additional serious health
effects beyond those that had been known when the 8-hour ozone health
standard was set. Since 1997, over 1,700 new health and welfare studies
relating to ozone have been published in peer-reviewed journals.\29\
Many of these studies have investigated the impact of ozone exposure on
such health effects as changes in lung structure and biochemistry,
inflammation of the lungs, exacerbation and causation of asthma,
respiratory illness-related school absence, hospital and emergency room
visits for asthma and other respiratory causes, and premature
mortality. EPA is currently in the process of evaluating these and
other studies as part of the ongoing review of the air quality criteria
and NAAQS for ozone. A revised Air Quality Criteria Document for Ozone
and Other Photochemical Oxidants will be prepared in consultation with
EPA's Clean Air Science Advisory Committee (CASAC). Key new health
information falls into four general areas: development of new-onset
asthma, hospital admissions for young children, school absence rate,
and premature mortality.
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\29\ New Ozone Health and Environmental Effects References,
Published Since Completion of the Previous Ozone AQCD, National
Center for Environmental Assessment, Office of Research and
Development, U.S. Environmental Protection Agency, Research Triangle
Park, NC 27711 (7/2002). A copy of this document is available in
Docket No. OAR 2002-0030.
---------------------------------------------------------------------------

Aggravation of existing asthma resulting from short-term ambient
ozone exposure was reported prior to the 1997 decision and has been
observed in studies published subsequently.30,31 In
particular, a relationship between long-term ambient ozone
concentrations and the incidence of new-onset asthma in adult males
(but not in females) was reported by McDonnell et al. (1999).\32\
Subsequently, an additional study suggests that incidence of new
diagnoses of asthma in children is associated with heavy exercise in
communities with high concentrations (i.e., mean 8-hour concentration
of 59.6 ppb) of ozone.\33\ This relationship was documented in children
who played 3 or more sports and thus had higher exposures and was not
documented in those children who played one or two sports. The larger
effect of high activity sports than low activity sports and an
independent effect of time spent outdoors also in the higher ozone
communities strengthened the inference that exposure to ozone may
modify the effect of sports on the development of asthma in some
children.
---------------------------------------------------------------------------

\30\ Thurston, G.D., M.L. Lippman, M.B. Scott, and J.M. Fine.
1997. Summertime Haze Air Pollution and Children with Asthma.
American Journal of Respiratory Critical Care Medicine, 155: 654-
660.
\31\ Ostro, B., M. Lipsett, J. Mann, H. Braxton-Owens, and M.
White (2001) Air pollution and exacerbation of asthma in African-
American children in Los Angeles. Epidemiology 12(2): 200-208.
\32\ McDonnell, W.F., D.E. Abbey, N. Nishino and M.D. Lebowitz.
1999. ``Long-term ambient ozone concentration and the incidence of
asthma in nonsmoking adults: the ahsmog study.'' Environmental
Research. 80(2 Pt 1): 110-121.
\33\ McConnell, R.; Berhane, K.; Gilliland, F.; London, S. J.;
Islam, T.; Gauderman, W. J.; Avol, E.; Margolis, H. G.; Peters, J.
M. (2002) Asthma in exercising children exposed to ozone: a cohort
study. Lancet 359: 386-391.
---------------------------------------------------------------------------

Previous studies have shown relationships between ozone and
hospital admissions in the general population. A study in Toronto
reported a significant relationship between 1-hour maximum ozone
concentrations and respiratory hospital admissions in children under
the age of two.\34\ Given the relative vulnerability of children in
this age category, we are particularly concerned about the findings.
---------------------------------------------------------------------------

\34\ Burnett, R. T.; Smith--Doiron, M.; Stieb, D.; Raizenne, M.
E.; Brook, J. R.; Dales, R. E.; Leech, J. A.; Cakmak, S.; Krewski,
D. (2001) Association between ozone and hospitalization for acute
respiratory diseases in children less than 2 years of age. Am. J.
Epidemiol. 153: 444-452.
---------------------------------------------------------------------------

Increased respiratory diseases that are serious enough to cause
school absences have been associated with 1-hour daily maximum and 8-
hour average ozone concentrations in studies conducted in Nevada \35\
in kindergarten to 6th grade and in Southern California in grades 4
through 6.\36\ These studies suggest that higher ambient ozone levels
may result in increased school absenteeism.
---------------------------------------------------------------------------

\35\ Chen, L.; Jennison, B. L.; Yang, W.; Omaye, S. T. (2000)
Elementary school absenteeism and air pollution. Inhalation Toxicol.
12:997-1016.
\36\ Gilliland, FD, K Berhane, EB Rappaport, DC Thomas, E Avol,
WJ Gauderman, SJ London, HG Margolis, R McConnell, KT Islam, JM
Peters (2001) The effects of ambient air pollution on school
absenteeism due to respiratory illnesses Epidemiology 12:43-54.
---------------------------------------------------------------------------

The air pollutant most clearly associated with premature mortality
is PM, with dozens of studies reporting such an association. However,
repeated ozone exposure is a possible contributing factor for premature
mortality, causing an inflammatory response in the lungs which may
predispose elderly and other sensitive individuals to become more
susceptible to other stressors, such as PM.37,38,39 Although
the findings have been mixed, the findings of three recent analyses
suggest that ozone exposure is associated with increased mortality.
Although the National Morbidity, Mortality, and Air Pollution Study
(NMMAPS) did not report an effect of ozone on total mortality across
the full year, the investigators who conducted the NMMAPS study did
observe an effect after limiting the analysis to summer when ozone
levels are highest.40,41 Similarly, other studies have shown
associations between ozone and mortality.42,43 Specifically,
Toulomi et al. (1997) found that 1-hour maximum ozone levels were
associated with daily numbers of deaths in 4 cities (London, Athens,
Barcelona, and Paris), and a quantitatively similar effect was found in
a group of four additional cities (Amsterdam, Basel, Geneva, and
Zurich).
---------------------------------------------------------------------------

\37\ Samet JM, Zeger SL, Dominici F, Curriero F, Coursac I,
Dockery DW, Schwartz J, Zanobetti A. 2000. The National Morbidity,
Mortality and Air Pollution Study: Part II: Morbidity, Mortality and
Air Pollution in the United States. Research Report No. 94, Part II.
Health Effects Institute, Cambridge, MA, June 2000. (Docket Number
A-2000-01, Document Nos. IV-A-208 and 209).
\38\ Devlin, R. B.; Folinsbee, L. J.; Biscardi, F.; Hatch, G.;
Becker, S.; Madden, M. C.; Robbins, M.; Koren, H. S. (1997)
Inflammation and cell damage induced by repeated exposure of humans
to ozone. Inhalation Toxicol. 9: 211-235.
\39\ Koren HS, Devlin RB, Graham DE, Mann R, McGee MP, Horstman
DH, Kozumbo WJ, Becker S, House DE, McDonnell SF, Bromberg, PA.
1989. Ozone-induced inflammation in the lower airways of human
subjects. Am. Rev. Respir. Dies. 139:407-415.
\40\ Samet JM, Zeger SL, Dominici F, Curriero F, Coursac I,
Dockery DW, Schwartz J, Zanobetti A. 2000. The National Morbidity,
Mortality and Air Pollution Study: Part II: Morbidity, Mortality and
Air Pollution in the United States. Research Report No. 94, Part II.
Health Effects Institute, Cambridge MA, June 2000. (Docket Number A-
2000-01, Documents No. IV-A-208 and 209)
\41\ Samet JM, Zeger SL, Dominici F, Curriero F, Coursac I,
Zeger, S. Fine Particulate Air Pollution and Mortality in 20 U.S.
Cities, 1987-1994. The New England Journal of Medicine. Vol. 343,
No. 24, December 14, 2000. P. 1742-1749.
\42\ Thurston, G. D.; Ito, K. (2001) Epidemiological studies of
acute ozone exposures and mortality. J. Exposure Anal. Environ.
Epidemiol. 11: 286-294.
\43\ Touloumi, G.; Katsouyanni, K.; Zmirou, D.; Schwartz, J.;
Spix, C.; Ponce de Leon, A.; Tobias, A.; Quennel, P.; Rabczenko, D.;
Bacharova, L.; Bisanti, L.; Vonk, J. M.; Ponka, A. (1997) Short-term
effects of ambient oxidant exposure on mortality: a combined
analysis within the APHEA project. Am. J. Epidemiol. 146: 177-185.
---------------------------------------------------------------------------

In all, the new studies that have become available since the 8-hour
ozone standard was adopted in 1997 continue to demonstrate the harmful
effects of ozone on public health, and the need to attain and maintain
the NAAQS.
b. Current and projected 8-hour ozone levels. The current primary
and secondary ozone NAAQS is 0.12 ppm daily maximum 1-hour
concentration, not to be exceeded more than once per year on average.
EPA is replacing the previous 1-hour ozone standard with a new 8-hour
standard. The new standard

[[Page 56234]]

is set at a concentration of 0.08 parts per million (ppm), and the
measurement period is 8 hours. Areas are allowed to disregard their
three worst measurements every year and average performance over three
years to determine if they meet the standard. That is, the standard is
set by the 4th highest maximum 8-hour concentration.
As shown earlier (Figure III-1) unhealthy ozone concentrations
exceeding the level of the 8-hour standard (i.e., not requisite to
protect the public health with an adequate margin of safety) occur over
wide geographic areas, including most of the nation's major population
centers. These monitored areas include much of the eastern half of the
U.S. and large areas of California.
Based upon data from 1999-2001, there are 291 counties where 111
million people live that are measuring values that violate the 8-hour
ozone NAAQS.\44\ An additional 37 million people live in 155 counties
that have air quality measurements within 10 percent of the level of
the standard.\45\ These areas, though currently not violating the
standard, would also benefit from the additional emission reductions
from this proposed rule.
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\44\ Additional counties may have levels above the NAAQS but do
not currently have monitors.
\45\ Memorandum to Docket A-2001-11 from Fred Dimmick, Group
Leader, Air Trends Group, ``Summary of Currently Available Air
Quality Data and Ambient Concentrations for Ozone and Particulate
Matter,'' December 3, 2002. A copy of this document is available in
Docket No. OAR 2002-0030.
---------------------------------------------------------------------------

From air quality modeling performed for the recent Nonroad Diesel
Engines and Fuel Control proposed rule,\46\ we anticipate that without
emission reductions beyond those already required under promulgated
regulation and approved State Implementation Plans (SIPs), ozone
nonattainment will likely persist into the future. With reductions from
programs already in place, the number of counties violating the ozone
8-hour standard is expected to decrease in 2020 to 30 counties where 43
million people are projected to live. Thereafter, exposure to unhealthy
levels of ozone is expected to begin to increase again. In 2030 the
number of counties violating the ozone 8-hour NAAQS is projected to
increase to 32 counties where 47 million people are projected to live.
In addition, in 2030, 82 counties where 44 million people are projected
to live will be within 10 percent of violating the ozone 8-hour NAAQS.
---------------------------------------------------------------------------

\46\ See the Regulatory Impact Analysis: ``Draft Regulatory
Impact Analysis: Control of Emissions from Nonroad Diesel Engines,''
EPA420-R-03-008, April 2003. This document is available at http://
www.epa.gov/nonroad/. A copy of this document can also be found in
Docket No. A-2001-28.
---------------------------------------------------------------------------

EPA is still developing the implementation process for bringing the
nation's air into attainment with the ozone 8-hour NAAQS. On June 2,
2003 (68 FR 32802), EPA issued a proposal for the implementation
process to bring the nation's air into attainment with the 8-hour ozone
NAAQS.\47\ The proposal seeks comment on options for planning and
control requirements, along with options for making the transition from
the 1-hour ozone standard to the 8-hour ozone standard. The proposal
does not designate nonattainment area for the 8-hour ozone NAAQS; EPA's
current plans calls for designating 8-hour ozone nonattainment areas in
April 2004, under a separate process. EPA has proposed that States
submit SIPs that address how areas will attain the 8-hour ozone
standard within 3 years after nonattainment designation for moderate
and above areas classified under subpart 2 and for some areas
classified under subpart 1. EPA is also proposing that marginal areas
and some areas designated under subpart 1 (i.e., those with early
attainment dates) will not be required to submit attainment
demonstrations for the 8-hour ozone standard. We therefore anticipate
that States will submit their attainment demonstration SIPs by April
2007.
---------------------------------------------------------------------------

\47\ A copy of this proposed rule entitled, ``Proposed Rule to
Implement the 8-Hour Ozone National Ambient Air Quality Standard.''
is available at: http://www.epa.gov/ttn/naaqs/ozone/o3imp8hr.
---------------------------------------------------------------------------

The Act contains two sets of requirements--subpart 1 and subpart
2--that establish requirements for State plans implementing the
national ozone air quality standards in nonattainment areas. (Both are
found in title I, part D.) Subpart 1 contains general requirements for
SIPs for nonattainment areas for any pollutant--including ozone--
governed by a NAAQS. Subpart 2 provides more specific requirements for
ozone nonattainment SIPs. Under subpart 1 of part D, title I of the Act
demonstrate that the nonattainment areas will attain the ozone 8-hour
standard as expeditiously as practicable but no later than five years
from the date that the area was designated nonattainment. However,
based on the severity of the air quality problem and the availability
and feasibility of control measures, the Administrator may extend the
attainment date ``for a period of no greater than 10 years from the
date of designation as nonattainment.'' Based on these provisions, we
expect that most or all areas covered under subpart 1 will attain the
ozone standard in the 2007 to 2014 time frame. For areas covered under
subpart 2, the maximum attainment dates provided under the Act range
from 3 to 20 years after designation, depending on an area's
classification. Thus, we anticipate that areas covered by subpart 2
will attain in the 2007 to 2024 time period.
Since the emission reductions expected from this proposed rule
would occur during the time period when areas will need to attain the
standard under either option, projected reductions in aircraft engine
emissions would assist States in their effort to meet the new NAAQS.
Such reductions would help them attain and maintain the 8-hour NAAQS.
2. Particulate Matter
NO_X emitted at low altitude is also a precursor in the
formation of some nitrate particulate matter (PM) in the atmosphere
(mostly ammonium nitrate).48,49 Essentially all nitrate PM
is of such a diameter that it is respirable in humans. As discussed
earlier, aircraft account for over 1 percent of the total U.S. mobile
source NO_X emissions, and aircraft's contribution to
nationwide secondary PM from U.S. mobile source NO_X is
expected to relatively similar.\50\
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\48\ Secondary PM is formed when NO_X reacts with
ammonia in the atmosphere to yield ammonium nitrate particulate.
\49\ U.S. EPA, ``Nitrogen Oxides: Impacts on Public Health and
the Environment,'' EPA 452/R-97-002, August 1997. A copy of this
document is available in Docket No. OAR 2002-0030.
\50\ ``Benefits of Mobile Source NO_X Related
Particulate Matter Reductions,'' Systems Applications International,
EPA Contract No. 68-C5-0010, WAN 1-8, October 1996. A copy of this
document is available in Docket No. OAR-2002-0030. This report
concluded that, as a national average, each 100 tons of
NO_X emissions will result in about 4 tons of secondary PM
(conversion rate was about 0.04). This conversion rate varies from
region to region, and is greatest in the West.
---------------------------------------------------------------------------

Particulate matter represents a broad class of chemically and
physically diverse substances. It can be principally characterized as
discrete particles that exist in the condensed (liquid or solid) phase
spanning several orders of magnitude in size. PM₁₀ refers to
particles with an aerodynamic diameter less than or equal to a nominal
10 micrometers. Fine particles refer to those particles with an
aerodynamic diameter less than or equal to a nominal 2.5 micrometers
(also known as PM_2.5), and coarse fraction particles are
those particles with an aerodynamic diameter greater than 2.5 microns,
but less than or equal to a nominal 10 micrometers. Ultrafine PM refers
to particles with diameters of less than 100 nanometers (0.1
micrometers). The health and environmental effects of PM are associated
with fine PM fraction and, in some cases, to the size of the particles.

[[Page 56235]]

Specifically, larger particles (£10 [mu]m) tend to be removed
by the respiratory clearance mechanisms whereas smaller particles are
deposited deeper in the lungs. Also, particles scatter light
obstructing visibility.
The emission sources, formation processes, chemical composition,
atmospheric residence times, transport distances and other parameters
of fine and coarse particles are distinct. Fine particles are directly
emitted from combustion sources and are formed secondarily from gaseous
precursors such as oxides of nitrogen (NO_X). Fine particles
are generally composed of sulfate, nitrate, chloride, ammonium
compounds, organic carbon, elemental carbon, and metals. Aircraft
engines emit NO_X which react in the atmosphere to form
secondary PM_2.5 (namely ammonium nitrate). Combustion of
coal, oil, diesel, gasoline, and wood, as well as high temperature
process sources such as smelters and steel mills, produce emissions
that contribute to fine particle formation. In contrast, coarse
particles are typically mechanically generated by crushing or grinding.
They include resuspended dusts and crustal material from paved roads,
unpaved roads, construction, farming, and mining activities. These
coarse particles can be either natural in source such as road dust or
anthropogenic. Fine particles can remain in the atmosphere for days to
weeks and travel through the atmosphere hundreds to thousands of
kilometers, while coarse particles deposit to the earth within minutes
to hours and within tens of kilometers from the emission source.
The relative contribution of various chemical components to
PM_2.5 varies by region of the country. Data on
PM_2.5 composition are available from the EPA Speciation
Trends Network in 2001 and the Interagency Monitoring of PROtected
Visual Environments (IMPROVE) network in 1999 covering both urban and
rural areas in numerous regions of the U.S. These data show that
nitrates formed from NO_X also play a major role in the
western U.S., especially in the California area where it is responsible
for about a quarter of the ambient PM_2.5 concentrations.

a. Health Effects of PM _2.5

Scientific studies show ambient PM is associated with a series of
adverse health effects. These health effects are discussed in detail in
the EPA Criteria Document for PM as well as the draft updates of this
document released in the past year.51,52
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\51\ U.S. EPA (1996.) Air Quality Criteria for Particulate
Matter--Volumes I, II, and III, EPA, Office of Research and
Development. Report No. EPA/600/P-95/001a-cF. This material is
available electronically at http://www.epa.gov/ttn/oarpg/ticd.html.
Available in Docket A-99-06, Document Nos. IV-A-30, IV-A-31, and IV-
A-32.
\52\ U.S. EPA (2002). Air Quality Criteria for Particulate
Matter--Volumes I and II (Third External Review Draft) This material
is available electronically at http://cfpub.epa.gov/ncea/cfm/partmatt.cfm.
Available in Docket A-2001-28, Document Nos. II-A-98
and II-A-71.
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As described in these documents, health effects associated with
short-term variation in ambient particulate matter (PM) have been
indicated by epidemiologic studies showing associations between
exposure and increased hospital admissions for ischemic heart disease,
heart failure, respiratory disease, including chronic obstructive
pulmonary disease (COPD) and pneumonia. Short-term elevations in
ambient PM have also been associated with increased cough, lower
respiratory symptoms, and decrements in lung function. Short-term
variations in ambient PM have also been associated with increases in
total and cardiorespiratory daily mortality. Studies examining
populations exposed to different levels of air pollution over a number
of years, including the Harvard Six Cities Study and the American
Cancer Society Study suggest an association between exposure to ambient
PM_2.5 and premature mortality, including deaths attributed
to lung cancer.53,54 Two studies further analyzing the
Harvard Six Cities Study's air quality data have also established a
specific influence of mobile source-related PM_2.5 on daily
mortality \55\ and a concentration-response function for mobile source-
associated PM_2.5 and daily mortality.\56\
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\53\ Dockery, DW; Pope, CA, III; Xu, X; et al. (1993) An
association between air pollution and mortality in six U.S. cities.
N Engl J Med 329:1753-1759.
\54\ Pope, CA, III; Thun, MJ; Namboordiri, MM; et al. (1995)
Particulate air pollution as a predictor of mortality in a
prospective study of U.S. adults. Am J Respir Crit Care Med 151:669-
674.
\55\ Laden F; Neas LM; Dockery DW; et al. (2000) Association of
fine particulate matter from different sources with daily mortality
in six U.S. cities. Environ Health Perspect 108(10):941-947.
\56\ Schwartz J; Laden F; Zanobetti A. (2002) The concentration-
response relation between PM(2.5) and daily deaths. Environ Health
Perspect 110(10): 1025-1029.
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b. Current and Projected Levels

There are NAAQS for both PM₁₀ and PM_2.5.
Violations of the annual PM_2.5 standard are much more
widespread than are violations of the PM₁₀ standards. Figure
III-1 at the beginning of this air quality section highlighted monitor
locations measuring concentrations above the level of the NAAQS. As can
be seen from that figure, high ambient levels are widespread throughout
the country. Today's proposed aircraft NO_X standards should
contribute to attainment and maintenance of the existing PM NAAQS since
NO_X contributes to the secondary formation of
PM_2.5.
The NAAQS for PM_2.5 were established by EPA in 1997 (62
FR 38651, July 18, 1997). The short term (24-hour) standard is set at a
level of 65 [mu]g/m3 based on the 98th percentile
concentration averaged over three years. (This air quality statistic
compared to the standard is referred to as the ``design value.'') The
long-term standard specifies an expected annual arithmetic mean not to
exceed 15 [mu]g/m3 averaged over three years.
Current PM_2.5 monitored values for 1999-2001, which
cover counties having about 75 percent of the country's population,
indicate that at least 65 million people in 129 counties live in areas
where annual design values of ambient fine PM violate the
PM_2.5 NAAQS. There are an additional 9 million people in 20
counties where levels above the NAAQS are being measured, but there are
insufficient data at this time to calculate a design value in
accordance with the standard, and thus determine whether these areas
are violating the PM_2.5 NAAQS. In total, this represents 37
percent of the counties and 64 percent of the population in the areas
with monitors with levels above the NAAQS.\57\ Furthermore, an
additional 14 million people live in 41 counties that have air quality
measurements within 10 percent of the level of the standard. These
areas, although not currently violating the standard, would also
benefit from the additional reductions from this proposed rule in order
to help ensure long term maintenance.
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\57\ Memorandum to Docket A-2001-11 from Fred Dimmick, Group
Leader, Air Trends Group, ``Summary of Currently Available Air
Quality Data and Ambient Concentrations for Ozone and Particulate
Matter,'' December 3, 2002. A copy of this document is available in
Docket No. OAR 2002-0030.
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The air quality modeling performed for the recent Nonroad Diesel
Engines and Fuel Control proposed rule also indicates that similar
conditions are likely to continue to exist in the future

[[Page 56236]]

in the absence of additional controls.\58\ For example, in 2020 based
on emission controls currently adopted, we project that 66 million
people will live in 79 counties with average PM_2.5 levels
above 15 [mu]g/m3. In 2030, the number of people projected
to live in areas exceeding the PM_2.5 standard is expected to
increase to 85 million in 107 counties. An additional 24 million people
are projected to live in counties within 10 percent of the standard in
2020, which will increase to 64 million people in 2030.
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\58\ See the Regulatory Impact Analysis: ``Draft Regulatory
Impact Analysis: Control of Emissions from Nonroad Diesel Engines,''
EPA420-R-03-008, April 2003. This document is available at http://
www.epa.gov/nonroad/. A copy of this document can also be found in
Docket No. A-2001-28.
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While the final implementation process for bringing the nation's
air into attainment with the PM_2.5 NAAQS is still being
completed in a separate rulemaking action, the basic framework is well
defined by the statute. EPA's current plans call for designating
PM_2.5 nonattainment areas in late 2004. Following
designation, section 172(b) of the Clean Air Act allows states up to
three years to submit a revision to their state implementation plan
(SIP) that provides for the attainment of the PM_2.5
standard. Based on this provision, states could submit these SIPs as
late as the end of 2007. Section 172(a)(2) of the Clean Air Act
requires that these SIP revisions demonstrate that the nonattainment
areas will attain the PM_2.5 standard as expeditiously as
practicable but no later than five years from the date that the area
was designated nonattainment. However, based on the severity of the air
quality problem and the availability and feasibility of control
measures, the Administrator may extend the attainment date ``for a
period of no greater than 10 years from the date of designation as
nonattainment.'' Therefore, based on this information, we expect that
most or all areas will need to attain the PM_2.5 NAAQS in the
2009 to 2014 time frame, and then be required to maintain the NAAQS
thereafter.

B. Other Environmental Effects

The following section presents information on four categories of
public welfare and environmental impacts related to NO_X and
fine PM emissions: acid deposition, eutrophication of water bodies,
plant damage from ozone, and visibility impairment.
1. Acid Deposition
Acid deposition, or acid rain as it is commonly known, occurs when
NO_X and SO₂ react in the atmosphere with water,
oxygen, and oxidants to form various acidic compounds that later fall
to earth in the form of precipitation or dry deposition of acidic
particles.\59\ It contributes to damage of trees at high elevations and
in extreme cases may cause lakes and streams to become so acidic that
they cannot support aquatic life. In addition, acid deposition
accelerates the decay of building materials and paints, including
irreplaceable buildings, statues, and sculptures that are part of our
nation's cultural heritage. To reduce damage to automotive paint caused
by acid rain and acidic dry deposition, some manufacturers use acid-
resistant paints, at an average cost of $5 per vehicle--a total of $80-
85 million per year when applied to all new cars and trucks sold in the
U.S.
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\59\ Much of the information in this subsection was excerpted
from the EPA document, Human Health Benefits from Sulfate Reduction,
written under Title IV of the 1990 Clean Air Act Amendments, U.S.
EPA, Office of Air and Radiation, Acid Rain Division, Washington, DC
20460, November 1995. A copy of this document is available in Docket
No. OAR 2002-0030.
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Acid deposition primarily affects bodies of water that rest atop
soil with a limited ability to neutralize acidic compounds. The
National Surface Water Survey (NSWS) investigated the effects of acidic
deposition in over 1,000 lakes larger than 10 acres and in thousands of
miles of streams. It found that acid deposition was the primary cause
of acidity in 75 percent of the acidic lakes and about 50 percent of
the acidic streams, and that the areas most sensitive to acid rain were
the Adirondacks, the mid-Appalachian highlands, the upper Midwest and
the high elevation West. The NSWS found that approximately 580 streams
in the Mid-Atlantic Coastal Plain are acidic primarily due to acidic
deposition. Hundreds of the lakes in the Adirondacks surveyed in the
NSWS have acidity levels incompatible with the survival of sensitive
fish species. Many of the over 1,350 acidic streams in the Mid-Atlantic
Highlands (mid-Appalachia) region have already experienced trout losses
due to increased stream acidity. Emissions from U.S. sources contribute
to acidic deposition in eastern Canada, where the Canadian government
has estimated that 14,000 lakes are acidic. Acid deposition also has
been implicated in contributing to degradation of high-elevation spruce
forests that populate the ridges of the Appalachian Mountains from
Maine to Georgia. This area includes national parks such as the
Shenandoah and Great Smoky Mountain National Parks.
A study of emissions trends and acidity of water bodies in the
Eastern U.S. by the General Accounting Office (GAO) found that from
1992 to 1999 sulfates declined in 92 percent of a representative sample
of lakes, and nitrate levels increased in 48 percent of the lakes
sampled.\60\ The decrease in sulfates is consistent with emissions
trends, but the increase in nitrates is inconsistent with the stable
levels of nitrogen emissions and deposition. The study suggests that
the vegetation and land surrounding these lakes have lost some of their
previous capacity to use nitrogen, thus allowing more of the nitrogen
to flow into the lakes and increase their acidity. Recovery of
acidified lakes is expected to take a number of years, even where soil
and vegetation have not been ``nitrogen saturated,'' as EPA called the
phenomenon in a 1995 study.\61\ This situation places a premium on
reductions of NO_X (and SO_X) from all sources,
including aircraft engines, in order to reduce the extent and severity
of nitrogen saturation and acidification of lakes in the Adirondacks
and throughout the U.S.
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\60\ Acid Rain: Emissions Trends and Effects in the Eastern
United States, U.S. General Accounting Office, March, 2000 (GAO/
RCED-00-47). A copy of this document is available in Docket No. OAR
2002-0030.
\61\ Acid Deposition Standard Feasibility Study: Report to
Congress, EPA 430R-95-001a, October, 1995. A copy of this document
is available in Docket No. OAR-2002-0030.
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The NO_X reductions from today's action would help reduce
acid rain and acid deposition, thereby helping to reduce acidity levels
in lakes and streams throughout the country and help accelerate the
recovery of acidified lakes and streams and the revival of ecosystems
adversely affected by acid deposition. Reduced acid deposition levels
will also help reduce stress on forests, thereby accelerating
reforestation efforts and improving timber production. Deterioration of
our historic buildings and monuments, and of buildings, vehicles, and
other structures exposed to acid rain and dry acid deposition also will
be reduced, and the costs borne to prevent acid-related damage may also
decline. While the reduction in nitrogen acid deposition would be
roughly proportional to the reduction in NO_X emissions the
precise impact of today's action would differ across different areas.
2. Eutrophication and Nitrification
Eutrophication is the accelerated production of organic matter,
particularly algae, in a water body. This

[[Page 56237]]

increased growth can cause numerous adverse ecological effects and
economic impacts, including nuisance algal blooms, dieback of
underwater plants due to reduced light penetration, and toxic plankton
blooms. Algal and plankton blooms can also reduce the level of
dissolved oxygen, which can also adversely affect fish and shellfish
populations.
In 1999, NOAA published the results of a five year national
assessment of the severity and extent of estuarine eutrophication. An
estuary is defined as the inland arm of the sea that meets the mouth of
a river. The 138 estuaries characterized in the study represent more
than 90 percent of total estuarine water surface area and the total
number of U.S. estuaries. The study found that estuaries with moderate
to high eutrophication conditions represented 65 percent of the
estuarine surface area. Eutrophication is of particular concern in
coastal areas with poor or stratified circulation patterns, such as the
Chesapeake Bay, Long Island Sound, or the Gulf of Mexico. In such
areas, the ``overproduced'' algae tends to sink to the bottom and
decay, using all or most of the available oxygen and thereby reducing
or eliminating populations of bottom-feeder fish and shellfish,
distorting the normal population balance between different aquatic
organisms, and in extreme cases causing dramatic fish kills.
Severe and persistent eutrophication often directly impacts human
activities. For example, losses in the nation's fishery resources may
be directly caused by fish kills associated with low dissolved oxygen
and toxic blooms. Declines in tourism occur when low dissolved oxygen
causes noxious smells and floating mats of algal blooms create
unfavorable aesthetic conditions. Risks to human health increase when
the toxins from algal blooms accumulate in edible fish and shellfish,
and when toxins become airborne, causing respiratory problems due to
inhalation. According to the NOAA report, more than half of the
nation's estuaries have moderate to high expressions of at least one of
these symptoms--an indication that eutrophication is well developed in
more than half of U.S. estuaries.
In recent decades, human activities have greatly accelerated
nutrient inputs, such as nitrogen and phosphorous, causing excessive
growth of algae and leading to degraded water quality and associated
impairments of freshwater and estuarine resources for human uses.\62\
Since 1970, eutrophic conditions worsened in 48 estuaries and improved
in 14. In 26 systems, there was no trend in overall eutrophication
conditions since 1970.\63\ On the New England coast, for example, the
number of red and brown tides and shellfish problems from nuisance and
toxic plankton blooms have increased over the past two decades, a
development thought to be linked to increased nitrogen loadings in
coastal waters. Long-term monitoring in the U.S., Europe, and other
developed regions of the world shows a substantial rise of nitrogen
levels in surface waters, which are highly correlated with human-
generated inputs of nitrogen to their watersheds.
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\62\ Deposition of Air Pollutants to the Great Waters, Third
Report to Congress, June, 2000. A copy of this document is available
in Docket No. OAR 2002-0030.
\63\ Deposition of Air Pollutants to the Great Waters, Third
Report to Congress, June, 2000. Great Waters are defined as the
Great Lakes, the Chesapeake Bay, Lake Champlain, and coastal waters.
The first report to Congress was delivered in May, 1994; the second
report to Congress in June, 1997. A copy of this document is
available in Docket No. OAR 2002-0030.
---------------------------------------------------------------------------

Between 1992 and 1997, experts surveyed by National Oceanic and
Atmospheric Administration (NOAA) most frequently recommended that
control strategies be developed for agriculture, wastewater treatment,
urban runoff, and atmospheric deposition.\64\ In its Third Report to
Congress on the Great Waters, EPA reported that atmospheric deposition
contributes from 2 to 38 percent of the nitrogen load to certain
coastal waters.\65\ A review of peer reviewed literature in 1995 on the
subject of air deposition suggests a typical contribution of 20 percent
or higher.\66\ Human-caused nitrogen loading to the Long Island Sound
from the atmosphere was estimated at 14 percent by a collaboration of
Federal and State air and water agencies in 1997.\67\ The National
Exposure Research Laboratory, U.S. EPA, estimated based on prior
studies that 20 to 35 percent of the nitrogen loading to the Chesapeake
Bay is attributable to atmospheric deposition.\68\ The mobile source
portion of atmospheric NO_X contribution to the Chesapeake
Bay was modeled at about 30 percent of total air deposition.\69\
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\64\ Bricker, Suzanne B., et al., National Estuarine
Eutrophication Assessment, Effects of Nutrient Enrichment in the
Nation's Estuaries, National Ocean Service, National Oceanic and
Atmospheric Administration, September, 1999. A copy of this document
is available in Docket No. OAR 2002-0030.
\65\ Deposition of Air Pollutants to the Great Waters, Third
Report to Congress, June, 2000. A copy of this document is available
in Docket No. OAR 2002-0030.
\66\ Valigura, Richard, et al., Airsheds and Watersheds II: A
Shared Resources Workshop, Air Subcommittee of the Chesapeake Bay
Program, March, 1997. Available in Docket A-99-06, Document No. IV-
G-144.
\67\ The Impact of Atmospheric Nitrogen Deposition on Long
Island Sound, The Long Island Sound Study, September, 1997. A copy
of this document is available in Docket No. OAR-2002-0030.
\68\ Dennis, Robin L., Using the Regional Acid Deposition Model
to Determine the Nitrogen Deposition Airshed of the Chesapeake Bay
Watershed, SETAC Technical Publications Series, 1997.
\69\ Ibid.
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Deposition of nitrogen from aircraft engines contributes to
elevated nitrogen levels in waterbodies. The NO_X reductions
from the proposed standards would help reduce the airborne nitrogen
deposition that contributes to eutrophication of watersheds,
particularly in aquatic systems where atmospheric deposition of
nitrogen represents a significant portion of total nitrogen loadings.
3. Plant Damage From Ozone
Ground-level ozone can also cause adverse welfare effects.
Specifically, ozone enters the leaves of plants where it interferes
with cellular metabolic processes. This interference can be manifest
either as visible foliar injury from cell injury or death, and/or as
decreased plant growth and yield due to a reduced ability to produce
food. With fewer resources, the plant reallocates existing resources
away from root storage, growth and reproduction toward leaf repair and
maintenance. Plants that are stressed in these ways become more
susceptible to disease, insect attack, harsh weather and other
environmental stresses. Because not all plants are equally sensitive to
ozone, ozone pollution can also exert a selective pressure that leads
to changes in plant community composition.
Since plants are at the center of the food web in many ecosystems,
changes to the plant community can affect associated organisms and
ecosystems (including the suitability of habitats that support
threatened or endangered species and below ground organisms living in
the root zone). Given the range of plant sensitivities and the fact
that numerous other environmental factors modify plant uptake and
response to ozone, it is not possible to identify threshold values
above which ozone is toxic and below which it is safe for all plants.
However, in general, the science suggests that ozone concentrations of
0.10 ppm or greater can be phytotoxic to a large number of plant
species, and can produce acute foliar injury responses, crop yield loss
and reduced biomass production. Ozone concentrations below 0.10 ppm
(0.05 to 0.09 ppm) can produce these effects in more sensitive plant
species, and have the potential over a longer duration of

[[Page 56238]]

creating chronic stress on vegetation that can lead to effects of
concern such as reduced plant growth and yield, shifts in competitive
advantages in mixed populations, and decreased vigor leading to
diminished resistance to pests, pathogens, and injury from other
environmental stresses.
Studies indicate that these effects described here are still
occurring in the field under ambient levels of ozone. The economic
value of some welfare losses due to ozone can be calculated, such as
crop yield loss from both reduced seed production (e.g., soybean) and
visible injury to some leaf crops (e.g., lettuce, spinach, tobacco) and
visible injury to ornamental plants (i.e., grass, flowers, shrubs),
while other types of welfare loss may not be fully quantifiable in
economic terms (e.g., reduced aesthetic value of trees growing in Class
I areas).
As discussed earlier, aircraft engine emissions of NO_X
contribute to ozone. The proposed standards would aid in the reduction
of ozone and, therefore, help reduce crop damage and stress from ozone
on vegetation.
4. Visibility
The secondary PM NAAQS is designed to protect against adverse
welfare effects which includes visibility impairment. In 1997, EPA
established the secondary PM_2.5 NAAQS as equal to the
primary (health-based) NAAQS of 15 ug/m3 (based on a 3-year
average of the annual mean) and 65 ug/m3 (based on a 3-year
average of the 98th percentile of the 24-hour average value) (62 FR
38669, July 18, 1997). EPA concluded that PM_2.5 causes
adverse effects on visibility in various locations, depending on PM
concentrations and factors such as chemical composition and average
relative humidity. In 1997, EPA demonstrated that visibility impairment
is an important effect on public welfare and that unacceptable
visibility impairment is experienced throughout the U.S., in multi-
state regions, urban areas, and remote federal Class I areas. In many
cities having annual mean PM_2.5 concentrations exceeding
annual standard, improvements in annual average visibility resulting
from the attainment of the annual PM_2.5 standard are
expected to be perceptible to the general population. Based on annual
mean monitored PM_2.5 data, many cities in the Northeast,
Midwest, and Southeast as well as Los Angeles would be expected to
experience perceptible improvements in visibility if the
PM_2.5 annual standard were attained.
Furthermore, in setting the PM_2.5 NAAQS, EPA
acknowledged that levels of fine particles below the NAAQS may also
contribute to unacceptable visibility impairment and regional haze
problems in some areas, and section 169 of the Act provides additional
authorities to remedy existing impairment and prevent future impairment
in the 156 national parks, forests and wilderness areas labeled as
mandatory Federal Class I areas (62 FR 38680-81, July 18, 1997).
Visibility can be defined as the degree to which the atmosphere is
transparent to visible light.\70\ Fine particles with significant
light-extinction efficiencies include organic matter, sulfates,
nitrates, elemental carbon (soot), and soil. Size and chemical
composition of particles strongly affects their ability to scatter or
absorb light. Nitrates typically contribute 1 to 6 percent of average
light extinction on haziest days in rural Eastern U.S. locations.\71\
Visibility is important because it directly affects people's
enjoyment of daily activities in all parts of the country. Individuals
value good visibility for the well-being it provides them directly,
both in where they live and work, and in places where they enjoy
recreational opportunities. Visibility is also highly valued in
significant natural areas such as national parks and wilderness areas,
because of the special emphasis given to protecting these lands now and
for future generations.
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\70\ National Research Council, 1993. Protecting Visibility in
National Parks and Wilderness Areas. National Academy of Sciences
Committee on Haze in National Parks and Wilderness Areas. National
Academy Press, Washington, DC. This book can be viewed on the
National Academy Press Website at http://www.nap.edu/books/0309048443/
html/. See also U.S. EPA Air Quality Criteria Document
for Particulate Matter (1996) (available on the internet at http://
cfpub.epa.gov/ncea/cfm/partmatt.cfm) and Review of the National
Ambient Air Quality Standards for Particulate Matter: Policy
Assessment of Scientific and Technical Information. These documents
can be found in Docket A-99-06, Documents No. II-A-23 and IV-A-130-
32.
\71\ US EPA Trends Report 2001. This document is available on
the internet at http://www.epa.gov/airtrends/. A copy of this
document is available in Docket No. OAR 2002-0030.
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To quantify changes in visibility, we compute a light-extinction
coefficient, which shows the total fraction of light that is decreased
per unit distance. Visibility can be described in terms of visual range
or light extinction and is reported using an indicator called
deciview.\72\ In addition to limiting the distance that one can see,
the scattering and absorption of light caused by air pollution can also
degrade the color, clarity, and contrast of scenes.
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\72\ Visual range can be defined as the maximum distance at
which one can identify a black object against the horizon sky. It is
typically described in miles or kilometers. Light extinction is the
sum of light scattering and absorption by particles and gases in the
atmosphere. It is typically expressed in terms of inverse megameters
(Mm-1), with larger values representing worse visibility.
The deciview metric describes perceived visual changes in a linear
fashion over its entire range, analogous to the decibel scale for
sound. A deciview of 0 represents pristine conditions. Under many
scenic conditions, a change of 1 deciview is considered perceptible
by the average person.
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In addition, visibility impairment can be described by its impact
over various periods of time, by its source, and the physical
conditions in various regions of the country. Visibility impairment can
be said to have a time dimension in that it might relate to short-term
excursions or to longer periods (e.g., worst 20 percent of days and
annual average levels). Anthropogenic contributions account for about
one-third of the average extinction coefficient in the rural West and
more than 80 percent in the rural East. In the Eastern U.S., reduced
visibility is mainly attributable to secondarily formed particles,
particularly those less than a few micrometers in diameter. While
secondarily formed particles still account for a significant amount in
the West, primary emissions contribute a larger percentage of the total
particulate load than in the East.
Furthermore, it is important to note that even in those areas with
relatively low concentrations of anthropogenic fine particles, such as
the Colorado Plateau, small increases in anthropogenic fine particulate
concentrations can lead to significant decreases in visual range. This
is one of the reasons mandatory Federal Class I areas have been given
special consideration under the Clean Air Act.\73\
---------------------------------------------------------------------------

\73\ The Clean Air Act designates 156 national parks and
wilderness areas as mandatory Federal Class I areas for visibility
protection.
---------------------------------------------------------------------------

Taken together with other programs, reductions from this proposal
would help to improve visibility across the nation, including mandatory
Federal Class I areas.

C. Other Criteria Pollutants Affected by This Proposed Rule

The standards being proposed today would also help reduce levels of
nitrogen dioxide (NO₂), for which NAAQS have been
established. Currently, every area in the United States has been
designated to be in attainment with the NO₂ NAAQS.

IV. Description of Action

Under the authority of section 231 of the CAA, EPA today proposes
to adopt standards equivalent to ICAO's February 1999 NO_X
emission standards (these NO_X standards were adopted at
CAEP/4 in 1998 and approved by the ICAO Council in 1999) and March 1997
test

[[Page 56239]]

procedure amendments. Today's proposed emission standards and test
procedure amendments apply to commercial aircraft engines; no general
aviation or military engines are covered by today's proposal. The
commercial aircraft engines subject to today's proposed NO_X
standards are those gas turbine engines that are newly certified (and
designed) after the effective date of the proposed regulations. (Newly
manufactured or already certified engines built after the effective
date of the proposed regulations would not have to meet these
standards.) For the sake of consistency and harmonization, the
effective dates below for the proposed NO_X standards are
identical with those of the ICAO 1999 NO_X standards. The
proposed NO_X emission standards, test procedure amendments,
and their effective dates are described below.

A. What Emission Standards Are Under Consideration?

As discussed earlier in sections II and III of today's notice,
section 231(a)(2)(A) of the CAA authorizes EPA to establish emission
standards for aircraft engine emissions'' * * * which in [her]
judgment
causes, or contributes to, air pollution which may reasonably be
anticipated to endanger public health or welfare.'' The Administrator
may revise such standards from ``time to time.'' CAA section 231(b)
requires that any emission standards provide sufficient lead time ``to
permit the development and application of the requisite technology,
giving appropriate consideration to the cost of compliance within such
period.''
Today's rule proposes near-term standards that would go into effect
in 2004 to ensure future engines do not jeopardize recent or past
technology gains. These standards are equivalent to the CAEP/4
NO_X international consensus emissions standards for aircraft
engines adopted by ICAO's CAEP in 1998.\74\ EPA intends to promulgate
these standards by January 2004 in order to be consistent with U.S.
obligations under ICAO. At the same time, EPA anticipates establishing
more stringent NO_X standards in the future. EPA will
participate at CAEP/6 (sixth meeting of CAEP), which is scheduled in
February 2004, to establish more stringent international consensus
emission standards for aircraft engines. Such standards would likely be
a central consideration in a future EPA regulation of aircraft engine
emissions.
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\74\ ICAO, CAEP, Fourth Meeting, Montreal, Quebec, April 6-8,
1998, Report, Document 9720, CAEP/4. Copies of this document can be
obtained from the ICAO Web site located at http://www.icao.int.
---------------------------------------------------------------------------

We believe this two-step approach is the most appropriate means to
address emissions from aircraft engines in this rulemaking. It would
codify current practice, with no significant lead time, as a near-term
approach.\75\ EPA has authority to revise emission standards from
``time to time''. EPA intends to address more stringent emission
standards requiring more lead time in a future rulemaking (see section
IV.A.5. for further discussion of future standards).
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\75\ As described later, more information and greater lead time
would be necessary to require more stringent standards.
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1. Today's Proposed NO_X Standards
EPA proposes to adopt standards equivalent to ICAO's 1999
NO_X emission standards for newly certified aircraft gas
turbine engines (turbofan and turbojet engines) of rated thrust or
output greater than 26.7 kilonewtons (kN) with compliance dates as
follows: \76\
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\76\ This proposal includes standards for low-, mid, and high-
thrust engines (see below for further discussion of the different
standards based on the thrust of the engines).
---------------------------------------------------------------------------

For engines of a type or model of which that date of manufacture of
the first individual production model was after December 31, 2003:
(a) for engines with a pressure ratio of 30 or less:
(i) for engines with a maximum rated output of more than 89.0 kN:
NO_X = (19 + 1.6(rated pressure ratio))g/kN(rated output)
(ii) for engines with a maximum rated output of more than 26.7 kN
but not more than 89.0 kN:
NO_X = (37.572 + 1.6(rated pressure ratio)-0.2087(rated
output))g/kN(rated output)
(b) for engines with a pressure ratio of more than 30 but less than
62.5:
(i) for engines with a maximum rated output of more than 89.0 kN:

NO_X = (7 + 2.0(rated pressure ratio))g/kN(rated output)

(ii) for engines with a maximum rated output of more than 26.7 kN
but not more than 89.0 kN:
NO_X = (42.71 + 1.4286(rated pressure ratio)--
0.4013(rated output) + 0.00642(rated pressure ratio x rated output))g/
kN(rated output)
(c) for engines with a pressure ratio of 62.5 or more:

NO_X = (32 + 1.6(rated pressure ratio))g/kN(rated output).

The NO_X emission standards presented above are
equivalent to the ICAO NO_X standards that have an
implementation date of December 31, 2003.\77\
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\77\ ICAO's CAEP/4 NO_X standards became effective
July 19, 1999, and applicable as of November 4, 1999. December 31,
2003 is the implementation date for these standards. However, for
the purpose of this Notice the effective date is considered the
implementation date. (ICAO, ``Aircraft Engine Emissions,''
International Standards and Recommended Practices, Environmental
Protection, Annex 16, Volume II, Second Edition, July 1993--
Amendment 4, July 19, 1999.)
---------------------------------------------------------------------------

2. Proposed NO_X Standards for Newly Certified Mid- and High-
Thrust Engines
EPA is proposing to adopt NO_X standards for newly
certified mid- and high-thrust engines (those engines designed and
certified after the effective date of the proposed regulations, which
have a rated output or thrust greater than 89 kN) that generally
represent about a 16 percent reduction (or increase in stringency) from
the existing standard. (See section IV.A.1(a)(i) and IV.A.1(b)(i) above
for the standards for mid- and high-thrust engines.) More specifically,
at a rated pressure ratio of 30 the proposed NO_X standards
represent a 16 percent reduction from the existing standard. At rated
pressure ratios of 10 and 20, the proposed standards correspond to 27
and 20 percent reductions, respectively. In addition, at rated pressure
ratios of 40 and 50, the proposed NO_X standards signify 9
and 4 percent reductions, respectively. Also, the proposed and existing
standards are equivalent at a rated pressure ratio of 62.5. See Figure
IV.B-1 in section IV.B. for a comparison of the proposed NO_X
standards (equivalent to CAEP/4 standards) to the existing standards
(equivalent to CAEP/2 standards) .
3. Proposed NO_X Standards for Newly Certified Low-Thrust
Engines
For newly certified low-thrust engines (engines with a thrust or
rated output of more than 26.7 kN but not more than 89.0 kN), EPA is
today proposing to adopt near-term NO_X standards that are
different than the standards proposed for mid- and high-thrust engines
(engines with thrust greater than 89.0 kN).\78\ In addition to rated
pressure ratio, the proposed standards for low-

[[Page 56240]]

thrust engines would also be dependent on an engine's thrust or rated
output.\79\ (See section IV.A.1(a)(ii) and IV.A.1(b)(ii) for a
description of these different standards.) For example, at a rated
pressure ratio of 30 and a thrust of 58 kN (thrust level in the middle
of 26.7 kN and 89 kN), these proposed standards are an 8 percent
reduction (or increase in stringency) from the existing standard
compared to a 16 percent reduction for the proposed standards for mid-
and high-thrust engines.\80\
---------------------------------------------------------------------------

\78\ Today's proposed NO_X standards for low thrust or
small engines specify that engines with a rated output or thrust at
26.7 kN meet the existing standard, and engines with a rated output
at 89 kN meet the proposed (or CAEP/4) standards. For engines with
rated outputs or thrust levels between 26.7 and 89 kN, a linear
interpolation was made between the low range of the existing
standard and the high range of the proposed standard based upon the
rated output to determine the proposed NO_X limits for
such engines. Thus, thrust dependent standards are being proposed
for engines with rated output or thrust between 26.7 kN and 89 kN.
\79\ The proposed standards for mid- and high-thrust engines are
dependent only on an engine's rated pressure ratio.
\80\ Additional examples of the proposed standards for low-
thrust engines in comparison to the proposed standards for mid- and
high-thrust engines are provided below. At rated pressure ratios of
10 and 20 with a thrust of 58 kN, the proposed low-thrust engine
standards are a 14 and 10 percent reduction from the existing
standard, respectively. Whereas, at these same rated pressure
ratios, the proposed standards for mid- and high-thrust engines are
27 and 20 percent reductions.
In addition, at rated pressure ratios of 40 and 50 with a thrust
of 58 kN, these low-thrust engine standards signify a 5 and 2
percent reduction from the existing standard, respectively. In
comparison, at these same rated pressure ratios, the proposed
standards for mid- and high-thrust engines are 9 and 4 percent
reductions.
---------------------------------------------------------------------------

The existing standards were not set at a stringency level that
created a need for low-thrust engines to have different requirements,
but at the level of NO_X stringency proposed today different
requirements are considered necessary for such engines. Due to their
physical size, it is difficult to apply the best NO_X
reduction technology to low thrust or small engines. The difficulty
increases progressively as size is reduced (from around 89 kN).\81\ For
example, the relatively small combustor space and section height of
these engines creates constraints on the use of low NO_X fuel
staged combustor concepts which inherently require the availability of
greater flow path cross-sectional area than conventional
combustors.\82\ Also, fuel staged combustors need more fuel injectors,
and this need is not compatible with the relatively lower total fuel
flows of lower thrust engines. (Reductions in fuel flow per nozzle are
difficult to attain without having clogging problems due to the small
sizes of the fuel metering ports.) In addition, lower thrust engine
combustors have an inherently greater liner surface-to-combustion
volume ratio, and this requires increased wall cooling air flow. Thus,
less air would be available to obtain acceptable turbine inlet
temperature distribution and for emissions control.\83\ Since the
difficulties increase progressively as engine thrust size is reduced,
EPA believes it would be appropriate to make a graded change in
stringency of the proposed NO_X standards for low-thrust
engines.
---------------------------------------------------------------------------

\81\ ICAO/CAEP, Report of Third Meeting, Montreal, Quebec,
December 5-15, 1995, Document 9675, CAEP/3.
\82\ ``The burner section of an aircraft engine, which contains
the combustion chamber, burns a mixture of fuel and air, and
delivers the resulting gases to the turbine at a temperature which
will not exceed the allowable limit at the turbine inlet.'' (United
Technologies Pratt and Whitney, ``The Aircraft Gas Turbine Engine
and Its Operation,'' August 1998.)
\83\ ICAO/CAEP Working Group 3 (Emissions), ``Combined Report of
the Certification and Technology Subgroups,'' section 2.3.6.1,
Presented by the Chairman of the Technology Subgroup, Third Meeting,
Bonn, Germany, June 1995. A copy of this paper can be found in
Docket OAR-2002-0030.
---------------------------------------------------------------------------

4. Rationale of Proposed NO_X Standards for Newly Certified
Low-, Mid-, and High-Thrust Engines
The proposed standards for low-, mid-, and high-thrust engines,
which are equivalent to the CAEP/4 standards, ensure that new engine
designs would incorporate the existing combustor technology and would
not perform worse than today's current engines. EPA intends to
promulgate these standards by January 2004 in order to be consistent
with U.S. obligations under ICAO. (See section II.B for a discussion of
the obligation of ICAO's participating nations). At this time, there is
not sufficient lead time to require more stringent emission standards
than the CAEP/4 NO_X emission standards by January 2004. As
discussed later in section IV.A.5 for future standards, we are
deferring action on more stringent NO_X standards because
pursuant to section 231(b) of the CAA we need more time to better
understand the cost of compliance with such standards, and additional
cost data is expected to be available from CAEP/6 in February 2004 (see
section IV.A.5 for further discussion regarding lead time).
EPA believes that the proposed standards would not impose any
additional burden on manufacturers, because manufacturers are already
designing new engines to meet the ICAO international consensus
standards by 2004 (see section VII of today's action for further
discussion of regulatory impact). Even though the U.S. did not
immediately adopt the ICAO NO_X standards after 1999, engine
manufacturers have continued to make progress in reducing these
emissions. Today's proposed standards are aimed at assuring that this
progress is not reversed in the future.
5. Future NO_X Standards for Newly Certified Low-, Mid-, and
High-Thrust Engines
More stringent standards for low-, mid-, and high-thrust engines
will be necessary in the future. As discussed earlier in section III,
the growth in aircraft emissions is projected to occur at a time when
other mobile source categories are reducing emissions.\84\ The 1999 EPA
study of commercial aircraft activity in ten cities projected that the
aircraft NO_X emissions would double in some of these cities
by 2010, and the aircraft component of the regional mobile source
NO_X emissions in the ten cities would grow from a range of 1
to 4 percent that existed in 1990 to a range of 2 to 10 percent in
2010.\85\ (As indicated earlier, the above projections were made prior
to the tragic events of September 11, 2001, and the subsequent economic
downturn. A January 2003 report by the Department of Transportation
indicated that the combination of the September 11, 2001 terrorist
attacks and a cut-back in business travel had a significant and perhaps
long-lasting effect on air traffic demand. However, the FAA expects the
demand for air travel to recover, and then continue a long-term trend
of annual growth in the United States.) More recently, as discussed
earlier FAA reports that flights (or activity) of commercial air
carriers will increase by 18 percent by 2010 and 45 percent by
2020.\86\ Thus, based on these trends

[[Page 56241]]

more stringent NO_X standards than the proposed standards are
needed in the future to reduce aircraft NO_X emissions in
nonattainment areas.
---------------------------------------------------------------------------

\84\ The projected growth in aircraft emissions is not simply
from the number of operations, but it could also be attributed to
the change in the types of aircraft being operated. For example,
regional aircraft activity is growing (regional aircraft are
generally referred to as those aircraft with more than 19 but fewer
than 100 seats--regional jets and turboprops). In the U.S., traffic
flown by regional airlines increased about 20 percent in 1999 and is
expected to grow approximately 7 percent annually during the next
ten years, compared to 4 to 6 percent for the major airlines. In
addition, regional jets comprised about 25 percent of the regional
aircraft fleet in 2000, up from only 4.2 percent in 1996, and their
fraction of the fleet is expected to increase to nearly 50 percent
by 2011. Regional aircraft are 40 to 60 percent less fuel efficient
compared to larger narrow- and wide-body aircraft, and regional jets
are 10 to 60 percent less fuel efficient than turboprop aircraft.
However, fuel costs have less of an effect on the operating costs of
regional aircraft compared to large aircraft. In addition, regional
jets have historically operated at higher load factors than
turboprops due to their popularity with travelers. (R. Babikian, S.
P. Lukachko and I. A. Waitz, ``Historical Fuel Efficiency
Characteristics of Regional Aircraft from Technological,
Operational, and Cost Perspectives,'' Journal of Air Transport
Management, Volume 8, No. 6, pp. 389-400, Nov. 2002).
\85\ U.S. EPA, ``Evaluation of Air Pollutant Emissions from
Subsonic Commercial Jet Aircraft,'' April 1999, EPA420-R-99-013.
This study is available at http://www.epa.gov/otaq/aviation.htm. It
can also be found in Docket No. OAR-2002-0030.
\86\ The flight forecast data is based on FAA's Terminal Area
Forecast System (TAFS). TAFs is the official forecast of aviation
activity at FAA facilities. This includes FAA-towered airports,
federally-contracted towered airports, nonfederal towered airports,
and many non-towered airports. For detailed information on TAFS and
the air carrier activity forecasts see the following FAA Web site:
http://www.apo.data.faa.gov/faatafall.HTM. As of May 1,
2003, the aviation forecasts contained in TAFS for Fiscal Years 2002-2020
included the impact of the terrorists' attacks of September 11, 2001
and the recent economic downturn. However, these projections did not
fully reflect the ongoing structural changes occurring within the
aviation industry. A copy of the May 1, 2003 forecast summary report
for air carrier activity can be found in Docket No. OAR-2002-0030.
---------------------------------------------------------------------------

Further stringency of the NO_X standards would reduce the
expected growth in commercial aircraft emissions. The importance of
controlling aircraft emissions has grown in many areas (especially
areas not meeting the 1-hour and 8-hour ozone NAAQS) as controls on
other sources become more stringent and attainment of the NAAQS's has
still not been achieved. (Many airports in the U.S. are located in
nonattainment areas.\87\) As activity increases, aircraft would emit
increasing amounts of NO_X in many nonattainment areas, and
thus, aircraft emissions would further aggravate the problems in these
areas (either by emitting pollutants directly within a nonattainment
area or by contributing to regional transport emissions in an area
upwind of a nonattainment area). More stringent aircraft engine
NO_X standards would assist in alleviating these problems in
nonattainment areas, and they would aid in preventing future concerns
in areas currently designated as attainment (or maintenance) areas. In
addition, attainment or maintenance of the NAAQS requires that aircraft
engines be subject to a program of control compatible with their
significance as pollution sources.
---------------------------------------------------------------------------

\87\ For information on the geographic location of airports, see
the following U.S. Department of Transportation (Bureau of
Transportation Statistics) Web site: http://www.bts.gov/oai.
The report or database provided on the website entitled, ``Airport
Activity Statistics of Certificated Air Carriers: Summary Tables
2000,'' lists airports by community. In addition, see the following
EPA website for information on nonattainment areas for criteria
pollutants: http://www.epa.gov/oar/oaqps/greenbk.
---------------------------------------------------------------------------

EPA, therefore, is considering more stringent future standards,
beyond today's proposed standards. Leading up to CAEP/6 in February
2004, one of the objectives of CAEP (and/or the international aviation
community) is to consider more stringent aircraft engine standards than
CAEP/4 standards for all gaseous emissions, especially
NO_X.\88\ ICAO CAEP working groups are currently assessing
the technological feasibility, economic reasonableness, and
environmental benefit of imposing more stringent NO_X
emissions standards for aircraft engines beyond that which will become
effective in 2004 (CAEP/4 standards). Options being considered range
from 5 to 30 percent more stringent with an effective date as early as
2008 to 2012 (these options are accompanied by more stringent standards
for low-thrust engines).\89\ Based on the results of this assessment, a
proposal for more stringent NO_X standards is expected to be
made at CAEP/6.\90\ (No changes to the standards of other pollutants,
hydrocarbons and carbon monoxide, are anticipated.) Activity is also
underway to identify and assess the potential for long-term technology
goals to be established for further emissions reductions.\91\ \92\ The
aim of the goal setting activity is to complement the ICAO CAEP
standard setting process with information to aid the engine and
airframe manufacturer's design process. The goals are expected to take
into account the results of recently completed emissions reduction
technology programs such as those conducted by National Aeronautics and
Space Administration (NASA) and the European Commission and the
timeline necessary to carry those technologies from the research phase
through commercialization.\93\ EPA is currently working with FAA and
CAEP working groups (as described in section V) in the evaluation of
NO_X stringency options for CAEP/6 and the potential for
long-term technology goals.
---------------------------------------------------------------------------

\88\ ICAO, CAEP, Fifth Meeting, Montreal, Quebec, January 1-17,
2001, ``Report on Agenda Item 4,'' CAEP/5-WP/86, January 17, 2001.
Copies of this document can be obtained from ICAO (http://www.icao.int).
\89\ ICAO, CAEP, Steering Group Meeting, Paris, France,
September 10-13, 2002, ``Summary of Discussions and Decisions of the
Second Meeting of the Steering Group,'' September 11, 2002, CAEP-
SG20022-SD/2. A copy of this paper can be found in Docket OAR-2002-
0030. Since this paper was written, the working groups have also
decided to consider the range of stringency options for an effective
date of 2008.
\90\ ICAO, CAEP, Steering Group Meeting, Paris, France,
September 10-13, 2002, ``Summary of Discussions and Decisions of the
First Meeting of the Steering Group,'' September 10, 2002, CAEP-
SG20022-SD/1. A copy of this paper can be found in Docket OAR-2002-
0030.
\91\ ICAO, CAEP, Fifth Meeting, Montreal, Quebec, January 1-17,
2001, ``Report on Agenda Item 4,'' CAEP/5-WP/86, January 17, 2001.
Copies of this document can be obtained from ICAO (http://www.icao.int).
\92\ For the purpose of setting long-term technology goals,
activity on the below tasks was initiated after CAEP/5 in 2001, and
it is expected to continue beyond CAEP/6.
(a) characterize emissions performance of future technologies
being pursued under national and international research programs,
including technology readiness;
(b) develop methodologies for quantifying aviation emissions
inventories;
(c) develop forecasts of emission trends both locally and
globally; and
(d) examine how such goals might be applied within the current
regulatory regime.
\93\ ICAO, CAEP, Fourth Meeting, Montreal, Quebec, April 6-8,
1998, Report, Document 9720, CAEP/4, see Appendix A to the Report on
Agenda Item 4 (page 4-A-1). Copies of this document can be obtained
from ICAO (http://www.icao.int).
---------------------------------------------------------------------------

Manufacturers should be able to achieve additional reductions with
more lead time than is provided by today's proposal. After CAEP/6, we
would assess whether or not the new international consensus and longer-
term standards (which are expected to be adopted) would be stringent
enough to protect the U.S. public health and welfare. If so, we would
propose to adopt the CAEP/6 NO_X standards soon thereafter.
EPA (or the U.S.) retains the discretion to adopt more stringent
standards in the future if the international consensus standards
ultimately prove insufficient to protect U.S. air quality.
Deferring consideration of more stringent future standards until
after CAEP/6 would allow us to obtain important additional information
on the costs of such standards.\94\ As described earlier in this
notice, section 231 of the CAA authorizes EPA from ``time to time'' to
revisit emission standards, and it requires that any standards'
effective dates permit the development of necessary technology, giving
appropriate consideration to the cost. We are not proposing more
stringent NO_X standards today primarily because we need more
time to better understand the cost of compliance of such standards, and
additional cost data is expected to be available from CAEP/6 in
February 2004. Producing (and/or developing) new engines or engine
technologies requires significant financial investments from engine
manufacturers, which takes time to recoup (the amount of time depends
upon sales of engines, replacement parts, etc.). As discussed earlier,
CAEP working groups are currently analyzing the costs and emission
benefits (taking into account lead time) for the options of further
NO_X stringency (beyond the CAEP/4 standards) being
considered for CAEP/6.\95\ After evaluating such

[[Page 56242]]

information, we would then be better situated to make decisions on an
appropriate level of stringency and implementation timing that
maximizes emission reductions from aircraft engines, taking into
consideration cost.
---------------------------------------------------------------------------

\94\ For low-thrust engines, deferring regulatory action on more
stringent future standards until after CAEP/6 would also enable us
to obtain additional information on the technological feasibility of
such standards.
\95\ Specifically, the Forecasting and Economic Analysis Support
Group (FESG) is conducting an analysis of the costs and emission
benefits for the further stringency options.
---------------------------------------------------------------------------

In addition, if we address more stringent future standards in
accordance with CAEP/6 action, we would have the benefits of
harmonizing with international standards.\96\ Due to the international
nature of the aviation industry, setting NO_X standards at
the appropriate level to meet U.S. air quality needs through
international consensus provides the potential for greater
environmental benefits. Aircraft and aircraft engines are international
commodities, and they are designed and built to meet international
standards. Adoption of international standards ensures emission
reductions from domestic and foreign aircraft in the U.S. In addition,
international consensus standards lead to air quality benefits in the
U.S. and throughout the world.
---------------------------------------------------------------------------

\96\ As discussed earlier, the U.S. has an obligation to be
compatible with the ICAO program if deemed appropriate.
---------------------------------------------------------------------------

B. Already Certified, Newly Manufactured Engines

Under current rules, the proposed NO_X standards would
not apply to already certified, newly manufactured engines (in-
production engines or engines built after the effective date of the
proposed standards), and the rationale for not applying these standards
to already certified low-, mid-, and high-thrust engines is discussed
below. Nearly all already certified engines (94 percent of in-
production engine models in the ICAO Aircraft Engine Exhaust Emissions
Data Bank \97\) currently meet or perform better than the standards we
are proposing to adopt today.\98\ (See Figure IV.B-1 below for a
comparison of the NO_X emission levels of current in-
production engines to the CAEP/4 NO_X standards.) \99\ At the
time the CAEP/4 NO_X standards were adopted in 1998, all but
11 in-production engines and 5 newly designed engine models (these 5
engines were in the design and development process in 1998) had
NO_X emission levels that would perform better than the CAEP/
4 standards.\100\ Based on a recent CAEP working group (specifically,
the Forecasting and Economic Analysis Support Group--FESG) analysis of
applying the CAEP/4 standards to already certified engines (at dates 2,
4, and 6 years after the implementation date for newly certified
engines), from those 16 engine models identified in 1998 today there
are only 4 already certified engine models or two engine families
remaining that would not meet the CAEP/4 standards.\101\ The other
engine models have either, through additional testing or modifications,
been improved to meet the standards or the engines are no longer in-
production.\102\ (There is only one remaining newly designed engine
model--out of the five identified in 1998--that may be certified after
2003, and thus, it would need to meet the CAEP/4 or proposed standards
for newly certified engines, which are effective beginning in
2004.)\103\
---------------------------------------------------------------------------

\97\ International Civil Aviation Organization (ICAO), Aircraft
Engine Exhaust Emissions Data Bank, July 2002. This data bank is
available at http://www.caa.co.uk/default.aspx?categoryid=702
&pagetype=90. In addition, a
copy of a table including data of engine NO_X emissions
from the ICAO data bank and their margin to the proposed
NO_X standards can be found in Docket OAR-2002-0030.
\98\ 116 out of 124 (94 percent) engine models that are
currently in production perform better than the CAEP/4
NO_X standards. The 8 engine models (which are mid- and
high-thrust engines) that are not achieving the CAEP/4
NO_X standards are from three different Pratt and Whitney
(PW) engine types or families (engines and their thrust variants
with the same build standard). These engines are the following: (1)
JT8D-217C E-kit and JT8D-219 E-kit; (2) PW4077D, PW4084D, and
PW4090; and (3) PW4164, PW4168, and PW4168A. (See Figure IV.B-1
below that specifically shows these 8 in-production models in
relation to the CAEP/4 or proposed NO_X standards.) For
the year 2000, these 8 engine models were found on approximately 751
out of 20,137 (3.7 percent) aircraft owned by U.S. carriers and
accounted for approximately 1,541,172 out of 11,505,063 (13.4
percent) of U.S. domestic flights.
(The above reference for the fleet fraction is BACK Aviation
Solutions, http://www.backaviation.com/Information_Services/default.htm.
The domestic flight information is based on SAGE, the System for
Assessing Aviation Emissions. SAGE is an FAA model that estimates
aircraft emissions through the full flight profile using non-
proprietary input data, such as BACK, FAA's Enhanced Traffic
Management System (ETMS), and the Official Airline Guide (OAG). The
year 2000 air traffic movements database portion of SAGE was used to
estimate the number of flights using the subject engines.)
\99\ For Figure IV.B-1, the Allison, Rolls-Royce, and Textron
Lycoming engines with rated pressure ratios less than 20 and
NO_X perform better than the standards, since there are
different CAEP/4 NO_X standards for these low-thrust
engines (see section IV.A.3 for further discussion of NO_X
standards for low thrust engines). (16 of the 124 engines, 13
percent of engine models in production, in Figure IV.B-1 and the
ICAO Aircraft Engine Exhaust Emissions Data Bank are low--thrust
engines--engines with thrust greater than 26.7 kN but not more than
89 kN.)
\100\ ICAO, CAEP/4, Working Paper 4, ``Economic Assessment of
the EPG NO_X Stringency Proposal,'' March 12, 1998,
Presented by the Chairman of Forecasting and Economic Analysis
Support Group (FESG), Agenda Item 1: Review of proposals relating to
NO_X emissions, including the amendment of Annex 16,
Volume II, See Table 3.1 of paper. A copy of this paper can be found
in Docket OAR-2002-0030.
\101\ CAEP Steering Group Meeting, ``FESG Economic Assessment of
Applying a Production Cut-Off To the CAEP/4 NO_X
Standard'', Presented by the FESG Co-Rapporteurs, Paris, September
10-13, 2002 (CAEP-SG20022-WP/20, September 12, 2002). The remaining
already certified engine models are the JT8D-217C, JT8D-219,
PW4084D, and PW4090. A copy of this paper can be found in Docket
OAR-2002-0030.
\102\ Only the first and second engine types of the three PW
types described earlier would not meet the CAEP/4 NO_X
standards if they were applied to newly manufactured or already
certified engines. The PW4077D is a derated version of the PW4084D,
and it is essentially considered the same engine. In addition, the
PW4077D has a NO_X level that is 0.2 percent greater than
the CAEP/4 standards. FESG rounded this margin to zero and
considered the PW4077D to be meeting the NO_X levels of
the CAEP/4 standards. The third engine type--PW4164, PW4168 and
PW4168A engines--are now certified with the PW 4168 Technologically
Affordable Low NO_X (Talon) II engine combustor
technology, which performs significantly better than the CAEP/4
standards.
\103\ The PW Canada growth engine is the one remaining newly
designed engine model. The ICAO Aircraft Engine Exhaust Emissions
Data Bank currently does not have emissions certification data for
such an engine, and thus, we anticipate that the PW Canada growth
engine would still be affected by the proposed standards. Yet, due
to the CAEP/4 standards already established, we expect that PW
Canada has already planned modifications for this engine or any
other newly certified engines to meet today's proposed standards.

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[[Page 56243]]

[GRAPHIC]
[TIFF OMITTED]
TP30SE03.001

*89 out of 124 (72 percent) of the in-production engines have
greater than 10 percent margin to the proposed (or CAEP/4)
NO_X standards. 56 (45 percent) of the engines have more
than 20 percent margin. 18 (15 percent) of the engines have greater
than 30 percent margin.

The recent FESG analysis indicates that the environmental benefit
(or NO_X emissions reduction) of applying the CAEP/4
NO_X standards to already certified engines, which would only
affect these 4 remaining engines, would be very small. As mentioned
earlier, the remaining four already certified (or in-production)
engines that perform worse than the CAEP/4 or proposed standards are
the following Pratt and Whitney (PW) mid- and high-thrust engines:
JT8D-217C, JT8D-219, PW4084D, and PW4090. The in-production JT8D-217C
and JT8D-219 engines could potentially apply to future supersonic
business jets, and the aircraft application for PW4084D and 4090
engines would be the Boeing 777-200s and -300s. Since business jets
have a very low utilization (about 100 to 200 annual departures per
aircraft), the emission reductions from potential new JT8D-217C and
JT8D-219 applications would be very small irregardless of the size of
the supersonic business jet market. If the potential JT8D-217C and
JT8D-219 supersonic business jets were to capture the entire projected
supersonic business jet market (200 to 400 aircraft over a 10 year
period or 20 to 40 aircraft per year), the total estimated annual
departures would be about 2,000 to 8,000. For the years 2005 and 2010,
there are estimated to be from 23 to 27 million departures from the
global passenger aircraft fleet (the potential supersonic business jet
market could potentially be about .01 to .03 percent of these global
fleet departures), so the resulting NO_X emission benefits
would be very small.\104\ In regard to Boeing 777 aircraft with
PW4084D/4090 engines, the incremental departures for such aircraft are
projected to be no greater than 0.1 percent per year (up to 25,500
departures in 2010); therefore, the resulting NO_X emissions
reductions would also be considered very small. (The FESG assessment
also showed that the costs of applying the CAEP/4 standards to already
certified engines would be relatively small on an industry wide basis.)
\105\ Consequently, we would expect there to be minimal environmental
benefit to also apply the proposed and CAEP/4 NO_X standards
for newly certified engines to already certified, newly manufactured
engines for an effective date after 2003 (the implementation date of
today's proposed standards is December 31, 2003).
---------------------------------------------------------------------------

\104\ CAEP Steering Group Meeting, ``FESG Economic Assessment of
Applying a Production Cut-Off To the CAEP/4 NO_X
Standard'', Presented by the FESG Co-Rapporteurs, Paris, September
10-13, 2002 (CAEP-SG20022-WP/20, September 12, 2002). In particular,
see Table 5.1 entitled, ``Excerpt from FESG CAEP/5 Traffic and Fleet
Mix Forecast.'' A copy of this paper can be found in Docket OAR-
2002-0030.
\105\ The costs of applying CAEP/4 standards to already
certified engines would impact just one engine manufacturer.
---------------------------------------------------------------------------

Also, if an already certified engine design meets the standards
that we are proposing today, then it is unlikely that either existing
or future engine designs built to that design or type (derivatives or
thrust variants with the same build standard) would not meet these
standards. When design modifications are made to an existing engine
type, then this engine type would likely need to be re-certified. A re-
certified engine type would be required to comply with the CAEP/4 and
new proposed NO_X standards.
For the remaining 4 engines (or two engine families) being built
that do not meet the CAEP/4 standards, Pratt and Whitney has other in-
production engine models (potentially derived versions or thrust
variants of engines with the same

[[Page 56244]]

build standard) or replacement/alternative engines that perform better
than the proposed NO_X standards and that are also similar in
size and aircraft application.\106\ For example, the PW 4098 engine
would achieve the NO_X levels of the proposed standards, and
similar to the PW4090 it is utilized on the Boeing 777-200 and 777-300.
Due to the 1998 CAEP/4 NO_X standards, Pratt and Whitney has
recently certified and manufactured these other or replacement engines.
Also, based upon the CAEP/4 standards, they have already targeted
future (after 2003) engine designs for modification so that newly
certified or designed engines would meet today's proposed
NO_X standards. Therefore, it appears unlikely that a
substantial number of the 4 remaining engines would be built or sold in
the future, unless they were produced as spare engines (replacement
engines for existing aircraft instead of newly manufactured aircraft).
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\106\ Although the remaining 4 engines (or two engine families)
currently being built are expected to still be in production in year
2004, they would not be required to meet the proposed standards.
---------------------------------------------------------------------------

1. Effect of Market Forces
In 1998, FESG indicated at CAEP/4 that ``* * * market forces and
potential local/regional operating restrictions might encourage the
manufacturers to modify their existing products, so that they, too,
comply with the proposed stringency.''\107\ These modifications to in-
production engines would be considered ``voluntary environmental
enhancement.''\108\ Thus, there was significant consideration at CAEP/4
given to the effect that new NO_X standards for newly
certified engines would potentially have on in-production or already
certified engines. Many parties within CAEP and its working groups
consider market forces to have a real and tangible effect on newly
manufactured or already certified engines, even though such engines are
not required to comply with the new standards. We are unaware of any
new local/regional operating restrictions being implemented throughout
the world due to the CAEP/4 NO_X standards. However, it seems
some market forces from the CAEP/4 newly certified engine standards
have affected production engines since there are now only four in-
production engine models remaining from 1998 that would not meet the
CAEP/4 standards. The Agency solicits comment on the effect market
forces and potential local/regional operating restrictions might have
on manufacturers to modify in-production or already certified engines.
---------------------------------------------------------------------------

\107\ ICAO, CAEP/4, Working Paper 4, ``Economic Assessment of
the EPG NO_X Stringency Proposal,'' March 12, 1998,
Presented by the Chairman of FESG, Agenda Item 1: Review of
proposals relating to NO_X emissions, including the
amendment of Annex 16, Volume II, section 3.3.2 of the paper. A copy
of this paper can be found in Docket OAR-2002-0030.
\108\ However, FESG indicated that the ``* * * the development
of production engine emissions enhancements would only occur if the
market place showed enough interest in the enhancements or if the
failure to meet the proposed stringency became a competitive
disadvantage.'' (ICAO, CAEP/4, Working Paper 4, ``Economic
Assessment of the EPG NO_X Stringency Proposal,'' March
12, 1998, Presented by the Chairman of FESG, Agenda Item 1: Review
of proposals relating to NO_X emissions, including the
amendment of Annex 16, Volume II, section 5.6.2 of the paper. A copy
of this paper can be found in Docket OAR-2002-0030.
---------------------------------------------------------------------------

2. Impact of Existing Fleet Aircraft
An element of the emissions proposals made at CAEP/4 was to
increase NO_X stringency as far as possible without affecting
the existing fleet aircraft asset values, and this was proposed to be
achieved by applying the new stringency to new engine designs only
(newly certified engines).\109\ Two studies on whether the financial
value of existing aircraft assets were affected by the CAEP/2
NO_X standards were reviewed for CAEP/4, and the studies did
not reveal any correlation between approval of the CAEP/2 emissions
standards and aircraft values. Thus, FESG was unable to definitively
assess the effect CAEP/4 NO_X standards would have on fleet
aircraft values.\110\ (The scope of the two studies and their ground
rules were set by FESG.) These studies showed that a large number of
factors impact aircraft asset values.
---------------------------------------------------------------------------

\109\ ICAO, CAEP, Fourth Meeting, Montreal, Quebec, April 6-8,
1998, Report, Document 9720, CAEP/4. Copies of this document can be
obtained from ICAO (http://www.icao.int).
\110\ ICAO, CAEP/4, Working Paper 4, ``Economic Assessment of
the EPG NO_X Stringency Proposal,'' March 12, 1998,
Presented by the Chairman of FESG, Agenda Item 1: Review of
proposals relating to NO_X emissions, including the
amendment of Annex 16, Volume II, section 4 of the paper. A copy of
this paper can be found in Docket OAR-2002-0030.
---------------------------------------------------------------------------

3. Request for Comment on Applying the Proposed NO_X
standards to Already Certified Engines
As discussed earlier, FESG and CAEP working groups (specifically,
Working Group 3--Emissions Technical Issues Working Group) are
currently considering applying the 1998 CAEP/4 NO_X standards
to engines built to already certified engine designs. Today, we are
requesting comment on whether to apply the proposed NO_X
standards, which are equivalent to the CAEP/4 NO_X standards,
to already certified engines.\111\ Historically, EPA and ICAO have
applied aircraft engine emission standards to already certified engines
(or newly manufactured engines).\112\ Although there is expected to be
minimal environmental benefits (as well as relatively small costs) from
such a requirement, it would ensure that manufacturers could not
indefinitely produce existing engines that do not meet these standards
(four such in-production or already certified engines models exist
today).\113\
The implementation dates being analyzed by FESG and Working Group 3
for applying CAEP/4 standards to already certified engines are 2, 4,
and 6 years after December 31, 2003 (the implementation date for newly
certified engines). Based on the results of the complete assessment
(which are not yet available), FESG and Working Group 3 are expected to
recommend an implementation date for applying the CAEP/4 standards to
already certified engines at CAEP/6 in February 2004 (a decision on
this date is also expected at CAEP/6).\114\ If this requirement and
date is accepted at CAEP/6, EPA would plan to propose the new
requirement soon thereafter (see section IV.B. above for a discussion
of the emission benefit of applying the proposed standards to already
certified engines). We request comment on applying standards for
already certified engines at a date 2, 4, and 6 years after the
implementation date for new designs (2006, 2008, and 2010). Commenters
suggesting different dates should specify the date(s) they prefer and,
to the extent possible,

[[Page 56245]]

provide technical and other justification for such suggested dates.
---------------------------------------------------------------------------

\111\ Spare engines for existing aircraft would not be covered
by such a requirement.
\112\ EPA promulgated a HC standard in 1982 that applied to
newly manufactured engines beginning in 1984. Also, the original
ICAO NO_X, HC, and CO standards approved in 1981 applied
to newly manufactured engines starting in 1986. In 1997, EPA adopted
this CO standard, which was to be implemented later that same year
for newly manufactured engines. In addition, the March 24, 1993 ICAO
amendment to tighten the original NO_X standard by 20
percent (CAEP/2 standards), which EPA adopted in 1997, applied to
newly certified engines beginning in 1996 and newly manufactured
engines in 2000.
\113\ Nearly all engines built to already certified engine
designs are likely to be in compliance with the proposed
NO_X standards.
\114\ The FESG analysis mentioned earlier (CAEP-SG20022-WP/20,
September 12, 2002) addresses the impact of applying the CAEP/4
NO_X standards to already certified engines at 2, 4, and 6
years after the implementation date of the CAEP/4 standards for
newly certified engines. Yet, further assessment of the
NO_X emission reductions was requested by the Steering
Group for the next meeting in mid-2003. (ICAO, CAEP, Steering Group
Meeting, Paris, France, September 10-13, 2002, ``Summary of
Discussions and Decisions of the First Meeting of the Steering
Group,'' September 10, 2002, CAEP-SG20022-SD/1. See page 3. A copy
of this paper can be found in Docket OAR-2002-0030.
---------------------------------------------------------------------------

In addition, at this time the mobile sources (including aircraft
engines) regulated under the authority of the Clean Air Act (Title II--
Emission Standards for Moving Sources) have emission standards for
newly manufactured engines or vehicles. However, except for aircraft
engines, all current CAA mobile source programs involving new emission
standards apply to newly manufactured engines or vehicles based on the
certification model year (new standards apply to newly and already
certified engines or vehicles in the same year). In these programs, EPA
has incorporated emission averaging programs to make a more orderly
product phase-in and phase-out (the average emissions within a
manufacturer's product line is required to meet the applicable
standard, which allows a manufacturer to produce some engine families
with emission levels above the standard).\115\ However, averaging is
not part of the ICAO protocol, and it is not clear that it is of any
value here since most in-production engines already meet the proposed
standards. Nonetheless, we solicit comment on whether an emission
averaging program for such engines would be useful.
---------------------------------------------------------------------------

\115\ Typically, the calculations used for averaging are based
upon an engine families yearly production or sales (among other
characteristics--e.g., average power rating of engines families).
---------------------------------------------------------------------------

C. Amendments to Criteria on Calibration and Test Gases for Gaseous
Emissions Test and Measurement Procedures

In today's proposed rule, EPA proposes to incorporate by reference
ICAO's 1997 amendments to the criteria on calibration and test gases
for the test procedures of gaseous emissions (ICAO International
Standards and Recommended Practices Environmental Protection, Annex 16,
Volume II, ``Aircraft Engine Emissions,'' Second Edition, July 1993;
Amendment 3, March 20, 1997, Appendices 3 and 5) in 40 CFR 87.64.
ICAO's amendments, which became effective on March 20, 1997, apply to
subsonic (newly certified and newly manufactured or already certified
engines) and supersonic gas turbine engines. The proposed technical
changes would correct a few inconsistencies between the specifications
for carbon dioxide (CO₂) analyzers (Attachment B of
Appendices 3 and 5) and the calibration and test gases (Attachment D of
Appendices 3 and 5) of gaseous emissions. The test procedure amendments
incorporated by reference would be effective 60 days after the
publication of the final rule.
For CAEP/3 in 1995, the Russian Federation presented a working
paper entitled, ``Corrections to Annex 16, Volume II,'' that stated the
following: \116\

\116\ Russian Federation, ``Corrections to Annex 16, Volume
II,'' Agenda Item 2: Review of reports of working groups relating to
engine emissions and the development of recommendations to the
Council thereon, Working Paper 19, Presented by A.A. Gorbatko,
November 11, 1995 (distributed November 30, 1995), CAEP/3, Montreal,
December 5 to 15, 1995. A copy of this paper can be found in Docket
OAR-2002-0030.
---------------------------------------------------------------------------

According to CAEP/2 recommendations, in the list of calibration
and test gases (see the table in Attachment of Appendices 3 and 5)
``CO₂ in N₂'' was replaced with
``CO₂ in air'' gas. At the same time the following sub-
paragraph was newly introduced into Attachment B (Appendices 3 and
5) :
(g) The effect of oxygen (O₂) on the CO₂
analyzer response shall be checked. For a change from 0 percent
O₂ to 21 percent O₂ the response of a given
CO₂ concentration shall not change by more than 2 percent
of reading. If this limit cannot be met and appropriate correction
factor shall be applied.
Since the best way to carry out this checking procedure is to
calibrate the analyzer first with CO₂ in nitrogen and
then with CO₂ in air, both ``CO₂ in
N₂'' and ``CO₂ in air'' gases have to be
retained in the list. It seems then that ``CO in air,''
``CO₂ in air,'' ``NO in N₂'' and now
``CO₂ in N₂'' have to be replaced with ``CO in
zero air,'' ``CO₂ in zero air,'' ``CO₂ in zero
nitrogen'' and ``NO in zero nitrogen'' just by analogy with the
gaseous mixtures of different hydrocarbons diluted by zero air and
listed in the same table.

In addition, at CAEP/3 the United Kingdom then presented a working
paper on this same issue.\117\ They indicated that CAEP's Working Group
3 (Emissions Working Group) had accepted the above proposals of the
Russian Federation paper on correcting inconsistencies in the list of
calibration and test gases specified in Annex 16, Volume II, Attachment
D to Appendices 3 and 5, and Working Group 3 had recommended that these
proposals be presented at CAEP/3. The United Kingdom also recommended
the adoption of these Russian Federation proposals--to utilize
CO₂ in nitrogen gas mixture to check the effect of oxygen on
CO₂ analyzers. In addition, they recommended the
specification of all calibration and test gases required for all the
gaseous emissions tests required in Annex 16.
---------------------------------------------------------------------------

\117\ United Kingdom, ``Amendments to Annex 16, Volume II,
Attachment D to Appendices 3 and 5 (Calibration and Test Gases),''
Agenda Item 2: Review of reports of working groups relating to
engine emissions and the development of recommendations to the
Council thereon, Working Paper 20, Presented by M.E. Wright,
November 14, 1995 (distributed November 30, 1995), CAEP/3, Montreal,
December 5 to 15, 1995. A copy of this paper can be found in Docket
OAR-2002-0030.
---------------------------------------------------------------------------

At CAEP/3, the CAEP members agreed that the above amendments to the
calibration and test gases were justified, and thus, these amendments
were then adopted.\118\ In today's notice, EPA proposes to incorporate
by reference the amendments to the criteria on calibration and test
gases for the test procedures of gaseous emissions, because the changes
improve the test procedures by correcting inconsistencies and
distinguishing between calibration and test gases. The amendments would
include the following: (1) Listing all calibration gases separately
from test gases for HC, CO₂, CO and NO_X
analyzers, (2) changing ``N₂'' to ``zero nitrogen'' in
relation to the test gases for the HC and NO_X analyzers, (3)
adding ``CO₂ in zero nitrogen'' as a test gas for CO2
analyzer, (4) changing ``air'' to ``zero air'' in relation to the test
gas for CO and CO₂ analyzers, (5) revising the accuracy to
``+/- 1 percent'' for the ``propane in zero air'' test gas of HC
analyzer, (6) amending the accuracy to ``+/- 1 percent'' for the
``CO₂ in zero air'' test gas of CO₂ analyzer, (7)
adding the accuracy ``+/- 1 percent'' for the ``CO₂ in zero
nitrogen'' test gas of CO₂ analyzer, (8) changing accuracy
to ``+/- 1 percent'' for test gas of CO analyzer, and (9) revising
accuracy to ``+/- 1 percent'' for test gas of NO_X analyzer.
---------------------------------------------------------------------------

\118\ ICAO/CAEP, Report of Third Meeting, Montreal, Quebec,
December 5-15, 1995, Document 9675, CAEP/3.
---------------------------------------------------------------------------

Manufacturers are already voluntarily complying with ICAO's 1997
amendments to the criteria on calibration and test gases for the test
procedures of gaseous emissions. Thus, formal adoption of these ICAO
test procedure amendments would require no new action by manufacturers.
In addition, the existence of ICAO's requirements would ensure that the
costs of compliance (as well as the air quality impact) with these test
procedures would be minimal. (In the 1982 and 1997 final rules on
aircraft engine emissions (47 FR 58462, December 30, 1982 and 62 FR
25356, May 8, 1997, respectively), EPA incorporated by reference the
then-existing ICAO testing and measurement procedures for aircraft
engine emissions (ICAO International Standards and Recommended
Practices Environmental Protection, Annex 16, Volume II, ``Aircraft
Engine Emissions,'' First and Second Editions, Appendices 3 and 5 were
incorporated by reference in 40 CFR 87.64) in order to eliminate
confusion over minor differences in

[[Page 56246]]

procedures for demonstrating compliance with the U.S. and ICAO
standards.)

D. Correction of Exemptions for Very Low Production Models

Because of an editorial error, the section in the aircraft engine
emission regulations regarding exemptions for very low production
models is incorrectly specified (see section 40 CFR 87.7(b)(1) and
(2)). In the October 18, 1984 final rulemaking (49 FR 41000), EPA
intended to amend the low production engine provisions of the aircraft
regulations by revising paragraph (b) and deleting paragraphs (b)(1)
and (b)(2) in order to eliminate the maximum annual production limit of
20 engines per year. In the revisions to paragraph (b), EPA retained
the maximum total production limit of 200 units for aircraft models
certified after January 1, 1984.\119\ For Sec. 87.7(b), EPA today
proposes to correct this editorial error by eliminating paragraph
(b)(1) and (b)(2).
---------------------------------------------------------------------------

\119\ This action was taken in 1984 to provide greater
flexibility to manufacturers for scheduling engine production rates
during the final years.
---------------------------------------------------------------------------

As discussed further in the 1984 final rulemaking, this proposed
action would provide more flexibility for engine manufacturers in
scheduling during the last few engine production years. Also, the air
quality impact of eliminating the annual production limit would be very
small.

V. Coordination with FAA

The requirements contained in the notice are being proposed after
consultation with the Secretary of Transportation in order to assure
appropriate consideration of aircraft safety. Under section 232 of the
CAA, the Secretary of Transportation (DOT) has the responsibility to
enforce the aircraft emission standards established by EPA under
section 231.\120\ In addition, section 231(b) of the CAA states that
``[a]ny regulation prescribed under this section * * * shall take
effect (after consultation with the Secretary of Transportation) to
permit the development and application of the requisite technology,
giving appropriate consideration to the cost of compliance * * *.'' As
in past rulemakings and pursuant to the above referenced sections of
the CAA, EPA has coordinated with the Federal Aviation Administration
(FAA) of the DOT with respect to today's proposal.
---------------------------------------------------------------------------

\120\ Specifically, the FAA of the DOT has the responsibility to
enforce the aircraft emission standards established by EPA.
---------------------------------------------------------------------------

Moreover, FAA is the official U.S. delegate to ICAO. FAA agreed to
the 1997 and 1999 amendments at ICAO's Third and Fourth Meetings of the
Committee on Aviation Environmental Protection (CAEP 3 and 4) after
advisement from EPA.\121\ FAA and EPA are both members of the CAEP's
Working Group 3 (among others), whose objective was to evaluate
emissions technical issues and develop recommendations on such issues
for CAEP 3 and 4. After assessing emissions test procedure amendments
and new NO_X standards, Working Group 3 made recommendations
to CAEP on these elements. These recommendations were then considered
at the CAEP 3 and 4 meetings, respectively, prior to their adoption by
ICAO in 1997 and 1999.
---------------------------------------------------------------------------

\121\ The Third Meeting of CAEP (CAEP/3) occurred in Montreal,
Quebec from December 5 through 15 in 1995. CAEP/4 took place in
Montreal from April 6 through 8, 1998.
---------------------------------------------------------------------------

In addition, as discussed above, FAA would have the responsibility
to enforce today's proposed requirements. As a part of its compliance
responsibilities, FAA conducts the emission tests or delegates that
responsibility to the engine manufacturer, which is then monitored by
the FAA. Since the FAA does not have the resources or the funding to
test engines themselves, FAA selects engineers at each plant to serve
as representatives (called designated engineering representatives
(DERs)) for the FAA while the manufacturer performs the test
procedures. DERs' responsibilities include evaluating the test plan,
the test engine, the test equipment, and the final testing report sent
to FAA. DERs' responsibilities are determined by the FAA and today's
proposal would not affect their duties.

VI. Possible Future Aviation Emission Reductions (EPA/FAA Voluntary
Aviation Emissions Reduction Initiative)

There is growing interest, particularly at the state and local
level, in addressing emissions from aircraft and other aviation-related
sources. Such interest is often related to plans for airport expansion
which is occurring across the country. It is possible that other
approaches may provide effective avenues to achieve additional aviation
emission reductions, beyond EPA establishing aircraft engine emission
standards. The Agency invites comment on the potential approach for
additional reductions discussed below and any other approaches.
Concerns by state and local air agencies and environmental and
public health organizations about aviation emissions, led to EPA and
FAA signing a memorandum of understanding (MOU) in March 1998 agreeing
to work to identify efforts that could reduce aviation emissions.\122\
Since that time FAA and EPA have jointly chaired a national stakeholder
initiative whose goal is to develop a voluntary program to reduce
pollutants from aircraft and other aviation sources that contribute to
local and regional air pollution in the United States. The major
stakeholders participating in this initiative include representatives
of the aviation industry (passenger and cargo airlines and engine
manufacturers), airports, state and local air pollution control
officials, environmental organizations, and NASA.
---------------------------------------------------------------------------

\122\ FAA and EPA, ``Agreement Between Federal Aviation
Administration and Environmental Protection Agency Regarding
Environmental Matters Relating to Aviation,'' signed on March 24,
1998 by FAA's Acting Assistant Administrator for Policy, Planning,
and International Aviation, Louise Maillet, and EPA's Acting
Assistant Administrator for Air and Radiation, Richard Wilson. A
copy of this document can be found in Docket OAR-2002-0030.
---------------------------------------------------------------------------

Initially, the discussions with stakeholders focused on the
prospect of aircraft engine emission reduction retrofit kits, which
might be applied to certain existing aircraft engines.\123\ However, as
the initiative evolved, the focus was expanded by the stakeholders to
identify strategies for various types of ground service equipment (GSE)
in use at airports (e.g., baggage tugs and fuel trucks),\124\ in
addition to strategies to reduce aircraft emissions.\125\ Due to the
differences in time and technology that it takes to reduce aircraft
emissions versus that for GSE, the stakeholders are seeking to reach a
consensus on a distinctly two-step program to voluntarily achieve wide-
scale emissions reductions from GSE and aircraft. Near term efforts
will focus on emissions reductions from GSE, and long term efforts will
focus on reductions from aircraft.\126\
---------------------------------------------------------------------------

\123\ Two engine models were indeed certificated with emissions
retrofit kits, and a number of these engines have been purchased for
aircraft with the retrofit kits installed in their stock
configuration. However, retrofit kits have not to date provided
widescale emissions improvements because it seems they may have
limited applicability to certain engine types, small emission
benefits, and cost issues.
\124\ The stakeholders are now considering the impact, operation
and design of GSE at airports, with projects being undertaken at
several airports to reduce overall emissions.
\125\ Operational strategies, such as reducing the time in which
aircraft are in idle and taxi modes and the impact of auxiliary
power units (APUs) have also been considered.
\126\ The stakeholder program for aircraft emissions reductions
is viewed as a supplement to the traditional regulatory approach of
establishing engine emission standards.
---------------------------------------------------------------------------

The stakeholders are currently discussing a framework for reaching

[[Page 56247]]

consensus on the goals or targets for emissions reductions, timing,
accountability, State Implementation Plan implications (including
general conformity), and numerous other issues that have been raised
for GSE and aircraft emission reductions. If this initiative is
successful, an agreement would be reached among all the stakeholders on
a national voluntary aviation emissions reduction program. The
mechanism that could be used to codify or enforce an eventual agreement
has yet to be determined. The overall goal of the EPA/FAA voluntary
initiative is to develop a program that will achieve significant
national emission reductions.

VII. Regulatory Impacts

Aircraft engines are international commodities, and thus, they are
designed to meet international standards. Today's proposal would have
the benefit of establishing consistency between U.S. and international
emission standards and test procedures. Thus, an emission certification
test which meets U.S. requirements would also be applicable to all ICAO
requirements. Engine manufacturers are already developing improved
technology in response to the ICAO standards that match the standards
proposed here, and EPA does not believe that the costs incurred by the
aircraft industry as a result of the existing ICAO standards should be
attributed to today's proposed regulations (as discussed above, these
standards only apply to newly certified or designed engines, but not
already certified, newly manufactured or in-production engines). Also,
the test procedure amendments (revisions to criteria on calibration and
test gases) necessary to determine compliance are already being adhered
to by manufacturers during current engine certification tests.
Therefore, EPA believes that the proposed regulations would impose no
additional burden on manufacturers.
The existence of ICAO's requirements results in minimal cost as
well as air quality benefits from today's proposed requirements.\127\
Since aircraft and aircraft engines are international commodities,
there is significant commercial benefit to consistency between U.S. and
international emission standards and control program requirements.
Also, EPA's proposed adoption of the ICAO standards and related test
procedures would be consistent with our treaty obligations and
strengthen the U.S. position in future ICAO/CAEP processes related to
emission standards.
---------------------------------------------------------------------------

\127\ CAEP's Forecasting and Economic Analysis Support Group
(FESG) concluded at CAEP/4 that their assessment of these new
NO_X standards indicates that the direct costs of the
standards would be minimal, and the benefits would be modest. (ICAO,
CAEP/4, Working Paper 4, ``Economic Assessment of the EPG
NO_X Stringency Proposal,'' March 12, 1998, Presented by
the Chairman of FESG, Agenda Item 1: Review of proposals relating to
NO_X emissions, including the amendment of Annex 16,
Volume II. A copy of this paper can be found in Docket OAR-2002-
0030.
---------------------------------------------------------------------------

VIII. Public Participation

We request comment on all aspects of this proposal. This section
describes how you can participate in this process.

A. How Do I Submit Comments?

We are opening a formal comment period by publishing this document.
We will accept comments during the period indicated under DATES above.
If you have an interest in the proposed emission control program
described in this document, we encourage you to comment on any aspect
of this rulemaking. We also request comment on specific topics
identified throughout this proposal.
Your comments will be most useful if you include appropriate and
detailed supporting rationale, data, and analysis. Commenters are
especially encouraged to provide specific suggestions for any changes
to any aspect of the regulations that they believe need to be modified
or improved. You should send all comments, except those containing
proprietary information, to our Air Docket (see section I.C under
SUPPLEMENTARY INFORMATION before the end of the comment period.
If you submit proprietary information for our consideration, you
should clearly separate it from other comments by labeling it
``Confidential Business Information.'' You should also send it directly
to the contact person listed under FOR FURTHER INFORMATION CONTACT
instead of to the public docket. This will help ensure that no one
inadvertently places proprietary information in the docket. If you want
us to use your confidential information as part of the basis for the
final rule, you should send a nonconfidential version of the document
summarizing the key data or information. We will disclose information
covered by a claim of confidentiality only through the application of
procedures described in 40 CFR part 2. If you don't identify
information as confidential when we receive it, we may make it
available to the public without notifying you.

B. Will There Be a Public Hearing?

We will hold a public hearing on November 13, 2003 at the
Environmental Protection Agency, EPA East Building, Room Number 1153,
1201 Constitution Avenue, NW., Washington, DC 20004, Telephone: (202)
564-1682. The hearing will start at 10 a.m. local time and continue
until everyone has had a chance to speak.
If you would like to present testimony at the public hearing, we
ask that you notify the contact person listed under FOR FURTHER
INFORMATION CONTACT at least ten days before the hearing. You should
estimate the time you will need for your presentation and identify any
needed audio/visual equipment. We suggest that you bring copies of your
statement or other material for the EPA panel and the audience. It
would also be helpful if you send us a copy of your statement or other
materials before the hearing.
We will make a tentative schedule for the order of testimony based
on the notifications we receive. This schedule will be available on the
morning of the hearing. In addition, we will reserve a block of time
for anyone else in the audience who wants to give testimony.
We will conduct the hearing informally, and technical rules of
evidence won't apply. We will arrange for a written transcript of the
hearing and keep the official record of the hearing open for 30 days to
allow you to submit supplementary information. You may make
arrangements for copies of the transcript directly with the court
reporter.

IX. Statutory Authority

The statutory authority for today's proposal is provided by
sections 231 and 301(a) of the Clean Air Act, as amended, 42 U.S.C.
7571 and 7601. See section III of today's NPRM for discussion of how
EPA meets the CAA's statutory requirements.

X. Statutory and Executive Order Reviews

A. Executive Order 12866: Regulatory Planning and Review

Under Executive Order 12866 (58 FR 51735, October 4, 1993), the
Agency must determine whether this regulatory action is ``significant''
and therefore subject to Office of Management and Budget (OMB) review
and the requirements of the Executive Order. The order defines
``significant regulatory action'' as one that is likely to result in a
rule that may:
(1) Have an annual effect on the economy of $100 million or more or
adversely affect in a material way the economy, a sector of the
economy, productivity, competition, jobs, the environment, public
health or safety, or State, local, or tribal governments or
communities;

[[Page 56248]]

(2) Create a serious inconsistency or otherwise interfere with an
action taken or planned by another agency;
(3) Materially alter the budgetary impact of entitlements, grants,
user fees, or loan programs or the rights and obligations of recipients
thereof; or
(4) Raise novel legal or policy issues arising out of legal
mandates, the President's priorities, or the principles set forth in
the Executive Order.
EPA has determined that this rule is not a ``significant regulatory
action'' under the terms of Executive Order 12866 and is therefore not
subject to OMB review. Today's action would codify emission standards
that manufacturers currently adhere to (nearly all in-production
engines already meet the standards). The proposed standards are
equivalent to the ICAO international consensus standards. These
proposed standards would not impose any additional burden on
manufacturers because they are already designing new engines to meet
the ICAO standards. Thus, the annual effect on the economy of today's
proposed standards would be minimal, and none of the other thresholds
identified in the executive order would be triggered by this action.

B. Paperwork Reduction Act

This action does not impose any information collection burden under
provisions of the Paperwork Reduction Act, 44 U.S.C. 3501 et seq. Any
reporting and recordkeeping requirements associated with these
standards would be defined by the Secretary of Transportation in
enforcement regulations issued later under the provisions of section
232 of the Clean Air Act. Since most if not all manufacturers already
measure NO_X and report the results to the FAA, any
additional reporting and record keeping requirements associated with
FAA enforcement of these proposed regulations would likely be very
small.
Burden means the total time, effort, or financial resources
expended by persons to generate, maintain, retain, or disclose or
provide information to or for a Federal agency. This includes the time
needed to review instructions; develop, acquire, install, and utilize
technology and systems for the purposes of collecting, validating, and
verifying information, processing and maintaining information, and
disclosing and providing information; adjust the existing ways to
comply with any previously applicable instructions and requirements;
train personnel to be able to respond to a collection of information;
search data sources; complete and review the collection of information;
and transmit or otherwise disclose the information.
An agency may not conduct or sponsor, and a person is not required
to respond to a collection of information unless it displays a
currently valid OMB control number. The OMB control numbers for EPA's
regulations in 40 CFR are listed in 40 CFR part 9.

C. Regulatory Flexibility Act

The RFA generally requires an agency to prepare a regulatory
flexibility analysis of any rule subject to notice and comment
rulemaking requirements under the Administrative Procedure Act or any
other statute unless the agency certifies that the rule will not have a
significant economic impact on a substantial number of small entities.
Small entities include small businesses, small organizations, and small
governmental jurisdictions.
For purposes of assessing the impacts of today's rule on small
entities, small entity is defined as: (1) A small business that meet
the definition for business based on SBA size standards; (2) a small
governmental jurisdiction that is a government of a city, county, town,
school district or special district with a population of less than
50,000; or (3) a small organization that is any not-for-profit
enterprise which is independently owned and operated and is not
dominant in its field. The following table 1 provides an overview of
the primary SBA small business categories potentially affected by this
proposed regulation.

Table X.C-1--Primary SBA Small Business Categories Potentially Affected
by This Proposed Regulation
------------------------------------------------------------------------
Defined by SBA as a
Industry NAICS a codes small business if: b
------------------------------------------------------------------------
Manufacturers of new aircraft 336412 <1,000 employees
engines.
Manufacturers of new aircraft..... 336411 <1,500 employees
Scheduled air carriers, passenger 481 <1,500 employees
and freight.
------------------------------------------------------------------------
a North American Industry Classification System (NAICS)
b According to SBA's regulations (13 CFR part 121), businesses with no
more than the listed number of employees or dollars in annual receipts
are considered ``small entities'' for purposes of a regulatory
flexibility analysis.

After considering the economic impacts of today's proposed rule on
small entities, I certify that this action will not have a significant
economic impact on a substantial number of small entities. This
proposed rule will not impose any requirements on small entities.
Because of the limited classes of aircraft engines to which today's
proposed regulations apply, no small entities would be affected. Our
review of the list of manufacturers of commercial aircraft gas turbine
engines with rated thrust greater than 26.7 kN indicates that there are
no U.S. manufacturers of these engines that qualify as small
businesses. We are unaware of any foreign manufacturers with a U.S.-
based facility that would qualify as a small business. In addition, the
proposed rule will not impose significant economic impacts on engine
manufacturers. As discussed earlier, today's action would codify
emission standards that manufacturers currently adhere to (nearly all
in-production engines already meet the standards). The proposed
standards are equivalent to the ICAO international consensus standards.
These proposed standards would not impose any additional burden on
manufacturers because they are already designing new engines to meet
the ICAO standards. Also, the test procedure amendments (revisions to
criteria on calibration and test gases) necessary to determine
compliance are already being adhered to by manufacturers during current
engine certification tests. Therefore, EPA believes that the proposed
regulations would impose no additional burden on manufacturers. The
existence of ICAO's requirements results in minimal cost from today's
proposed requirements. We invite comments on all aspects of the
proposal and its impacts on small entities.

D. Unfunded Mandates Reform Act

Title II of the Unfunded Mandates Reform Act of 1995 (UMRA), Public
Law 104-4, establishes requirements for Federal agencies to assess the
effects of their regulatory actions on State, local, and tribal
governments and the private sector. Under section 202 of the UMRA, EPA
generally must prepare a written statement, including a cost-benefit
analysis, for proposed and final rules

[[Page 56249]]

with ``Federal mandates'' that may result in expenditures to State,
local, and tribal governments, in the aggregate, or to the private
sector, of $100 million or more in any one year. Before promulgating an
EPA rule for which a written statement is needed, section 205 of the
UMRA generally requires EPA to identify and consider a reasonable
number of regulatory alternatives and adopt the least costly, most
cost-effective or least burdensome alternative that achieves the
objectives of the rule. The provisions of section 205 do not apply when
they are inconsistent with applicable law. Moreover, section 205 allows
EPA to adopt an alternative other than the least costly, most cost-
effective or least burdensome alternative if the Administrator
publishes with the final rule an explanation why that alternative was
not adopted. Before EPA establishes any regulatory requirements that
may significantly or uniquely affect small governments, including
tribal governments, it must have developed under section 203 of the
UMRA a small government agency plan. The plan must provide for
notifying potentially affected small governments, enabling officials of
affected small governments to have meaningful and timely input in the
development of EPA regulatory proposals with significant Federal
intergovernmental mandates, and informing, educating, and advising
small governments on compliance with the regulatory requirements.
EPA has determined that this rule does not contain a Federal
mandate that may result in expenditure of $100 million or more for
State, local, or tribal governments, in the aggregate or the private
sector in any one year. This rule contains no regulatory requirements
that might significantly or uniquely affect small governments. Today's
action would codify emission standards that manufacturers currently
adhere to (nearly all in-production engines already meet the
standards). The proposed standards are equivalent to the ICAO
international consensus standards. These proposed standards would not
impose any additional burden on manufacturers because they are already
designing new engines to meet the ICAO standards. Thus, the annual
effect on the economy of today's proposed standards will be minimal.
Thus, today's rule is not subject to the requirements of sections 202
and 205 of the UMRA.

E. Executive Order 13132: Federalism

Executive Order 13132, entitled ``Federalism'' (64 FR 43255, August
10, 1999), requires EPA to develop an accountable process to ensure
``meaningful and timely input by State and local officials in the
development of regulatory policies that have federalism implications.''
``Policies that have federalism implications'' is defined in the
Executive Order to include regulations that have ``substantial direct
effects on the States, on the relationship between the national
government and the States, or on the distribution of power and
responsibilities among the various levels of government.''
This proposed rule does not have federalism implications. It will
not have substantial direct effects on the States, on the relationship
between the national government and the States, or on the distribution
of power and responsibilities among the various levels of government,
as specified in Executive Order 13132. As discussed earlier, section
233 of the CAA preempts states from adopting or enforcing aircraft
engine emission standards. This proposed rule merely modifies existing
EPA aircraft engine emission standards and test procedures and
therefore will merely continue an existing preemption of State and
local law. Thus, Executive Order 13132 does not apply to this rule.
In the spirit of Executive Order 13132, and consistent with EPA
policy to promote communications between EPA and State and local
governments, EPA specifically solicits comment on this proposed rule
from State and local officials.

F. Executive Order 13175: Consultation and Coordination with Indian
Tribal Governments

Executive Order 13175, entitled ``Consultation and Coordination
with Indian Tribal Governments'' (59 FR 22951, November 6, 2000),
requires EPA to develop an accountable process to ensure ``meaningful
and timely input by tribal officials in the development of regulatory
policies that have tribal implications.''
This proposed rule does not have tribal implications as specified
in Executive Order 13175. The proposed emission standards and other
related requirements for private industry in this rule have national
applicability and therefore do not uniquely affect the communities of
Indian Tribal Governments. As discussed earlier, section 233 of the CAA
preempts states from adopting or enforcing aircraft engine emission
standards. This proposed rule merely modifies existing EPA aircraft
engine emission standards and test procedures and therefore will merely
continue an existing preemption of State and local law. In addition,
this rule will be implemented at the Federal level and impose
compliance obligations only on engine manufacturers. Thus, Executive
Order 13175 does not apply to this rule. EPA specifically solicits
additional comment on this proposed rule from tribal officials.

G. Executive Order 13045: Protection of Children from Environmental
Health & Safety Risks

Executive Order 13045, ``Protection of Children from Environmental
Health Risks and Safety Risks'' (62 FR 19885, April 23, 1997) applies
to any rule that (1) is determined to be ``economically significant''
as defined under Executive Order 12866, and (2) concerns an
environmental health or safety risk that EPA has reason to believe may
have a disproportionate effect on children. If the regulatory action
meets both criteria, Section 5-501 of the Order directs the Agency to
evaluate the environmental health or safety effects of the planned rule
on children, and explain why the planned regulation is preferable to
other potentially effective and reasonably feasible alternatives
considered by the Agency.
This proposal is not subject to Executive Order 13045 because it is
not economically significant under the terms of Executive Order 12866,
and because the Agency does not have reason to believe the
environmental health or safety risks addressed by this action present a
disproportionate risk to children.
The effects of ozone and PM on children's health were addressed in
detail in EPA's rulemaking to establish NAAQS for these pollutants, and
EPA is not revisiting those issues here. EPA believes, however, that
the emission reductions (NO_X and secondary PM) from this
rulemaking will further reduce ozone and PM and the related adverse
impacts on children's health.
The public is invited to submit or identify peer-reviewed studies
and data, of which the agency may not be aware, that assessed results
of early life exposure to ozone and PM.

H. Executive Order 13211: Actions that Significantly Affect Energy
Supply, Distribution, or Use

This rule is not subject to Executive Order 13211, ``Actions
Concerning Regulations That Significantly Affect Energy Supply,
Distribution, or Use'' (66 FR 28355, May 22, 2001) because it is not a
significant regulatory action under Executive Order 12866.

I. National Technology Transfer Advancement Act

Section 12(d) of the National Technology Transfer and Advancement

[[Page 56250]]

Act of 1995 (``NTTAA''), Public Law 104-113, section 12(d) (15 U.S.C.
272 note) directs EPA to use voluntary consensus standards in its
regulatory activities unless to do so would be inconsistent with
applicable law or otherwise impractical. Voluntary consensus standards
are technical standards (e.g., materials specifications, test methods,
sampling procedures, and business practices) that are developed or
adopted by voluntary consensus standards bodies. NTTAA directs EPA to
provide Congress, through OMB, explanations when the Agency decides not
to use available and applicable voluntary consensus standards.
This proposed rulemaking involves technical standards for testing
emissions for commercial aircraft gas turbine engines. EPA proposes to
use test procedures contained in ICAO International Standards and
Recommended Practices Environmental Protection, with the proposed
modifications contained in this rulemaking.\128\ These procedures are
currently used by all manufacturers of commercial aircraft gas turbine
engines (with thrust greater than 26.7 kN) to demonstrate compliance
with ICAO emissions standards.
---------------------------------------------------------------------------

\128\ ICAO International Standards and Recommended Practices
Environmental Protection, Annex 16, Volume II, ``Aircraft Engine
Emissions,'' Second Edition, July 1993--Amendment 3, March 20, 1997.
Copies of this document can be obtained from ICAO (http://www.icao.int).
---------------------------------------------------------------------------

EPA welcomes comments on this aspect of the proposed rulemaking
and, specifically, invites the public to identify potentially-
applicable voluntary consensus standards and to explain why such
standards should be used in this regulation.

List of Subjects in 40 CFR Part 87

Environmental protection, Air pollution control, Aircraft,
Incorporation by reference.

Dated: September 12, 2003.
Marianne Lamont Horinko,
Acting Administrator.
For the reasons set out in the preamble, title 40, chapter I of the
Code of Federal Regulations is proposed to be amended as follows:

PART 87--CONTROL OF AIR POLLUTION FROM AIRCRAFT AND AIRCRAFT
ENGINES

1. The authority citation for part 87 continues to read as follows:

Authority: Secs. 231, 301(a), Clean Air Act, as amended (42
U.S.C 7571, 7601(a)).

Subpart A--[Amended]

2. Section 87.7 is amended by removing paragraphs (b)(1) and
(b)(2).

Subpart C--[Amended]

3. Section 87.21 is amended by adding paragraph (d)(1)(vi) to read
as follows:

Sec. 87.21 Standards for exhaust emissions.

* * * * *
(d) * * *
(1) * * *
(vi) Engines of a type or model of which the date of manufacture of
the first individual production model was after December 31, 2003:
(A) Engines with a rated pressure ratio of 30 or less:
(1) Engines with a maximum rated output greater than 89
kilonewtons:
Oxides of Nitrogen: (19 + 1.6(rPR)) grams/kilonewtons rO.
(2) Engines with a maximum rated output greater than 26.7
kilonewtons but not greater than 89 kilonewtons:
Oxides of Nitrogen: (37.572 + 1.6(rPR)-0.2087(rO)) grams/kilonewtons
rO.
(B) Engines with a rated pressure ratio greater than 30 but less
than 62.5:
(1) Engines with a maximum rated output greater than 89
kilonewtons:
Oxides of Nitrogen: (7 + 2(rPR)) grams/kilonewtons rO.
(2) Engines with a maximum rated output greater than 26.7
kilonewtons but not greater than 89 kilonewtons:
Oxides of Nitrogen: (42.71 + 1.4286(rPR) - 0.4013(rO) + 0.00642(rPR -
rO)) grams/kilonewtons rO.
(C) Engines with a rated pressure ratio of 62.5 or more:
Oxides of Nitrogen: (32 + 1.6(rPR)) grams/kilonewtons rO.
* * * * *

Subpart G--[Amended]

4. Section 87.64 is revised to read as follows:

Sec. 87.64 Sampling and analytical procedures for measuring gaseous
exhaust emissions.

The system and procedures for sampling and measurement of gaseous
emissions shall be as specified by Appendices 3 and 5 to International
Civil Aviation Organization (ICAO) Annex 16, Environmental Protection,
Volume II, Aircraft Engine Emissions, Second Edition, July 1993
(including Amendment 3 of March 20, 1997), which are incorporated
herein by reference. This incorporation by reference was approved by
the Director of the Federal Register in accordance with 5 U.S.C. 552(a)
and 1 CFR part 51. These materials are incorporated as they exist on
the date of the approval and a notice of any change in these materials
will be published in the Federal Register. Frequent changes are not
anticipated. Copies may be inspected at U.S. EPA, Air and Radiation
Docket and Information Center, 1301 Constitution Ave., NW., Room B102,
EPA West Building, Washington, DC 20460, or at the Office of the
Federal Register, 800 North Capitol Street, NW., 7th Floor, Suite 700,
Washington DC. Copies of this document can be obtained from the
International Civil Aviation Organization (ICAO), Document Sales Unit,
999 University Street, Montreal, Quebec, Canada H3C 5H7.
5. Section 87.71 is revised to read as follows:

Sec. 87.71 Compliance with gaseous emission standards.

Compliance with each gaseous emission standard by an aircraft
engine shall be determined by comparing the pollutant level in grams/
kilonewton/thrust/cycle or grams/kilowatt/cycle as calculated in Sec.
87.64 with the applicable emission standard under this part. An
acceptable alternative to testing every engine is described in Appendix
6 to International Civil Aviation Organization (ICAO) Annex 16,
Environmental Protection, Volume II, Aircraft Engine Emissions, Second
Edition, July 1993 (including Amendment 3 of March 20, 1997), which is
incorporated herein by reference. This incorporation by reference was
approved by the Director of the Federal Register in accordance with 5
U.S.C. 552(a) and 1 CFR part 51. These materials are incorporated as
they exist on the date of the approval and a notice of any change in
these materials will be published in the Federal Register. Frequent
changes are not anticipated. Copies may be inspected at U.S. EPA, Air
and Radiation Docket and Information Center, 1301 Constitution Ave.,
NW., Room B102, EPA West Building, Washington, DC 20460, or at the
Office of Federal Register, 800 North Capitol Street, NW., 7th Floor,
Suite 700, Washington DC. Copies of this document can be obtained from
the International Civil Aviation Organization (ICAO), Document Sales
Unit, 999 University Street, Montreal, Quebec, Canada H3C 5H7. Other
methods of demonstrating compliance may be approved by the Secretary
with the concurrence of the Administrator.
6. Section 87.82 is revised to read as follows:

[[Page 56251]]

Sec. 87.82 Sampling and analytical procedures for measuring smoke
exhaust emissions.

The system and procedures for sampling and measurement of smoke
emissions shall be as specified by Appendix 2 to International Civil
Aviation Organization (ICAO) Annex 16, Volume II, Environmental
Protection, Aircraft Engine Emissions, Second Edition, July 1993
(including Amendment 3 of March 20, 1997), which are incorporated
herein by reference. This incorporation by reference was approved by
the Director of the Federal Register in accordance with 5 U.S.C. 552(a)
and 1 CFR part 51. These materials are incorporated as they exist on
the date of the approval and a notice of any change in these materials
will be published in the Federal Register. Frequent changes are not
anticipated. Copies may be inspected at U.S. EPA, Air and Radiation
Docket and Information Center, 1301 Constitution Ave., NW., Room B102,
EPA West Building, Washington, DC 20460, or at the Office of the
Federal Register, 800 North Capitol Street, NW., 7th Floor, Suite 700,
Washington DC. Copies of this document can be obtained from the
International Civil Aviation Organization (ICAO), Document Sales Unit,
999 University Street, Montreal, Quebec, Canada H3C 5H7.
7. Section 87.89 is revised to read as follows:

Sec. 87.89 Compliance with smoke emission standards.

Compliance with each smoke emission standard shall be determined by
comparing the plot of SN as a function of power setting with the
applicable emission standard under this part. The SN at every power
setting must be such that there is a high degree of confidence that the
standard will not be exceeded by any engine of the model being tested.
An acceptable alternative to testing every engine is described in
Appendix 6 to International Civil Aviation Organization (ICAO) Annex
16, Environmental Protection, Volume II, Aircraft Engine Emissions,
Second Edition, July 1993 (including Amendment 3 of March 20, 1997),
which is incorporated herein by reference. This incorporation by
reference was approved by the Director of the Federal Register in
accordance with 5 U.S.C. 552(a) and 1 CFR part 51. These materials are
incorporated as they exist on the date of the approval and a notice of
any change in these materials will be published in the Federal
Register. Frequent changes are not anticipated. Copies may be inspected
at U.S. EPA, Air and Radiation Docket and Information Center, 1301
Constitution Ave., NW., Room B102, EPA West Building, Washington, DC
20460, or at the Office of the Federal Register, 800 North Capitol
Street, NW., 7th Floor, Suite 700, Washington DC. Copies of this
document can be obtained from the International Civil Aviation
Organization (ICAO), Document Sales Unit, 999 University Street,
Montreal, Quebec, Canada H3C 5H7.

[FR Doc. 03-24412 Filed 9-29-03; 8:45 am]
BILLING CODE 6560-50-P

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